Add to that, Mab says "The stars will rain from the sky before Mab fulfills not her word." This suggests to me that when "Empty Night" happens, Mab will fail her words or duty.

In the Mother Summer/Winter (MS/MW) cabin scene in CD, MS told MW that the possible bright futures must be better than a future of "Empty Night" even to her.

To me this strongly implies that the fruition of Nemesis's goals would be "Empty Night"

Here is another idea.  If the Outsiders are from a reality outside of our own, their imposition of their own reality upon ours would be the ultimate result of an Outsider sucessful invasion.

These 2 ideas together imply to me that "Empty Night" is what the Outsider Home reality is like.

Two points that tie directly to this line of thoughts. 
1.The main wampire expletive is "Empty Night" so they seem to have some kind of ties to this concept. 
2.We know the Final Dresden Files book will be called "Empty Night"

In Cold Days Harry also described the sky around the Outer Gates and the ongoing siege as being a starless, black sky. This would fit the "Empty Night" reference and definitely suggest the Outsiders involvement.

Agreed.  And Ill toss a third tie it to the list:  When Thomas quotes the bible verse regarding the weakness of the Wampires, he says:

Quote

"Love is patient. Love is kind. Love always forgives, trusts, supports, and endures. Love never fails. When every star in the heavens grows cold, and when silence lies once more on the face of the deep, three things will endure: faith, hope, and love."

"And the greatest of these is love," I finished. "That's from the Bible."

"First Corinthians, chapter thirteen," Thomas confirmed.

I looked around and confirmed (as much as I can) that those bits are not actually in any of the common translations of the Bible, so I think they are more foreshadowing.   Which would make the Faith/Hope/Love bit a fairly strong indication of the significance of the Swords, come BAT time)

Hells Bells, or at least the principle behind it, was seen briefly in Smf. The bells used to help power the greater circle against the Archive. Thinking that whole circle worked on similar principles and gross denial of freedom Powering Hells Bigger Bells, possibly they were actually tapping into it with the circle. So Hells Bells are used to confine. Then we have Thomas's empty night 'corinthians' quote about silence falling on the deeps, so the Bells are bad when they stop? Noteworthy to mention is EG calls Lucifer the darkest Shadow, the deeps are called shadowrealm, (shadow something anyway) and the lord of slowest terror hunter of the shadows. Now I can't remember if this bit is actually in the DV or if I'm confused because its a reacurring element in various other mythos, but iirc shadowrealm and dreamland are very close if not one within the other. (dream>shadow)

1) I'm not ready to connect the one mention of bells in the containment spell for Ivy to Hell's Bells.  It's an interesting concept though.  Specifically, I think the danger in Hell's Bells falling silent is that they herald the end.; they may be a sign of the/an apocalypse.  I'm not 100% that they're tied to Christian hell, however.  Either the BAT is the apocalypse for ALL religions, it's a crossover event of multiple apocalypses (apocalypsi?), or its the apocalypse for one but not the others.
     The bells falling silent, and leading to empty night, may not mean that there are bells currently ringing and holding something or someone prisoner. 
2) There are two deeps.  The first is the Raith cave nicknamed the Deeps.  The second is probably poetic verse for reality, and specifically the outer reaches or space. 
3) The ghoul in the WN flashback referred to the place where the ghouls come from as the "Realm of Shadows".  Lash confirms at the time that it's a region of the Nevernever.  We don't know for sure where it is, but my guess is the RoS is the place where Cowl launches his attacks from, which would be the same place that Peabody escaped to.  The connection between the two is the attack by the ghouls in WN, where they all came through, which appeared to be (but may not have been) the same place Cowl always comes from.  The gate in the Raith Deeps that the ghouls came from was the same as was used in the caves in New Mexico, which were described as reaching the RoS.  The kink in that theory is that Harry says that Cowl appears in his own gate, which may or may not have been from the same place that the ghouls came from.  Still, my money is that Cowl's hide-out is the RoS.
4) I don't know of a connection between the RoS and the dream pockets that wizards and others can create.  I think they're seperate.
5) Harry gets Mouse in BR.  We've never found out who kidnapped the pups. 
6) Harry mentions in TC that he "still had nightmares", specifically about Morgan.  And he mentions in Changes that he had nightmares of Sells, up until he upgraded.  It seems to imply to me that he still gets nightmares, but doesn't dwell on them in the books as much.
7) My interpretion of "the demon" in the Malcolm dream was that it was a representation of Lasciel's shadow, Lash.  Malcolm specifically says "You know what it is.  You know what it wants."  I don't think he would have been referring to Nemesis, which Harry wouldn't know about at the time.  Instead, I think its an illusion to the thing haunting him at the time, which is Lash.  She first appeared to him while dreaming/unconscious.  It makes sense that in a safe dream, she'd still be there, just not as prettily disguised.

Edit:
Also, I've been contemplating "Stars & Stones".  Empty Night, based on the hints we've seen, appears to refer to a period of darkness, where the stars won't be visible in the sky.  Part of me wonders about whether it will be a blanket of darkness around Earth, or if Earth gets pulled into the NN on some level, making the stars disappear.  Hell's Bell's, as I mentioned, I take to be a heralding to the Apocalypse.  I'm not sure if it's a specific threat in itself, so much as a sign.

S&S has two obvious connotations to me. 
     The first is the use of stones (like Stonehenge) to plot time using the heavens (the stars).  Typically done during the day using the sun, there are also Viking lodestones used to navigate at night under the stars. 
     The second is the idea that, on a much more galactic scale, all of reality is "stars and stones".  The stars are, duh, stars.  And all of the planets and meteors and such are nothing more than stones drifting through space. 
     It makes me wonder if the imagery is supposed to be local (stones on earth) or galactic (earth is stone).

Clarification on what’s behind the titles for the final trilogy.  
Hell’s Bells and Stars & Stones are Harry and Eb terms; Empty Night is used by Thomas.  They are curses for a reason.

So a lil background on Hells Bells from wiki-answers.
what is the origin of the idiom hell's bells?
-If you are unfortunate enough to get to, Hell, when you arrive there is a ceremony where new arrivals are required to ring bells, like church bells, to let all in Hell know you have arrived. In other words, Hell's bells, are what are rung to alert those that have been there a while, "You have company."

I know it contradicts my earlier theory but maybe Hells Bells do go off when we have outsider visitors?

On Stars and Stones, Something that struck me literally ten min ago as I reread changes. When Harry goes to the stone table there is very specifically 5 cold pure stars described as upon Lady nights throat(Hint hint!). I wonder if the phrase isn't connected to these stars and this stone table? conjecture, SNS will deal with how the table was made, how it works and why it can give power to a wellspring. possibly I'll have more later, I'm supposed to be asleep

Space is often referred to as DEEP space.  And in Genesis 1:2, "...Darkness was upon the face of the deep."

2) The cave on the Raith's property is nicknamed "The Deeps".  Space, as peregrine mentioned, is referred to as deep space when it's far out.  Similar to how Outside is far away.  And there's the biblical Deep that peregrine mentioned, which signified existence. 
3)  Agreed, but we can't be sure.  The portal Cowl usually opens mentions a dank smell.  The one he opened for himself in the Deeps had a red glow.  The one that the ghouls came through had the dank, mildewy smell normally associated with Cowl's gates, but was a dark oval, not a red glowing oval.
4) I was confused by your comment, but I think you mean the Eebs mentioned it.  I read it as Eb.  And Esmerelda mentions the Land of Dreams, which is where Mouse's line probably originated.  I don't think there's been any indication in the DV that the Ros and the LoD are anywhere near each other.  They may be, but we haven't had any indication yet.
5) I'm sure we'll find out more when Harry kills Mavra in the past.
6) Not that I can recall either.  Bu then again, he had sessions with Lash up until WN if I recall.  Those weren't 'invasive', but the only invasive dream I recall him having is the Nightmare in GP.  What other ones were there that were truly invasive, before Mouse?  Mouse was around for DB when Harry's dad showed up.  And the one you mentioned in DM didn't really seem to be a sending/invading dream; it seemed like a nightmare, and someone stepped in to help him rest.  It could have been his ghost mother, or possibly Lea or Mab.
7) That's why I think he was referring to Lash.  Why refer to two different threats, one that Harry's unaware of and has never knowingly encountered, and then another that's prevalent on his thoughts and concerns in that book?

2 Oh I was using DF references, which seems to go through a bit of length in BR to connect the corinthian paraphrase with the Raith deeps and the Raith deeps with the ROS. Deep space is actually a relatively newer concept of 4-500 yrs at the most. 3 Wasn't that because he used the spell on Harry's gate he glowed? I always assumed the light was a conjuration, even Cowl see's by light. 4 Yea I was thinking there was a small reference somewhere to it. Maybe I'm assuming because its that way in manga? Its part of the oriental beliefs somewhere. 5 LMAO? 6 Just had the thought, Harry got mouse soon after the strega started bringing Hwwbh back across the threshold. coincidence? 7 But Malcolm specifically says a fallen can't protect you. You got to pay attention to Harry's grammer (like mine when I say Merlin or The Merlin ) Dream Harry isn't split in this dream, he's subconscious Harry too. SubHarry knows The demon stalks him.

And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.

Santa is a much bigger and more powerful faery than Toot, and I don't know his true name anyway. You'd never see me trying to nab Saint Nick in a magic circle even if I did. I don't think anyone has stones that big.

The "Wyld Courts": There are a couple of powerful Sidhe on par with the Faerie Queens-the Earlking is on of them, and it's rumored-DON'T LAUGH!-that Santa Claus (a brownie Sidhe) may be another.

Priscillie asked Jim if the Erlking is Wyldfae at DragonCon and posted this reply:
Jim: He is wyldfae.  He isn't a subject of Mab or Titania.  That's what Wyldfae means.  But his origins are in the Summer-side of the cycle of seasons, just like Titania's are.
Ditto Santa, only in Winter. 
(He /is/ beholden to Mother Summer, but basically everyone in Faerie is, so.)
(I mean, that's like saying "you must obey the law of gravity."  Duh.)

Dudesan: You've described Santa Claus as being the Winter King. What does that title mean? Do Winter and Summer each have a trinity of Father/King/Prince, like they do with Mother/Queen/Lady? Is the King necessarily the consort of the Queen? If so, will we be seeing Oberon at some point?
Jim: 5) The Faerie realms just aren't that structured. It's more accurate to say that he is /a/ Winter King. Or even more accurately, that he is a free Wyld Fae who is of a power level that is on par with Mab's and happens to neighbor her sphere of influence, and finds it simpler to show up to family dinners during the holidays and make polite than to start staking out boundaries and establishing treaties.
Oberon... well, the guy kind of wound up between Mab and Titania in one of those romantic triangle things, back around Shakespeare's day. He didn't make it.

Is Kringle Fae?
Is Kringle Fae? His mantle, yes, is part of the Winter Court. Which does not necessarily mean that he himself is Fae as much as the fact that his mantle is. While he’s there, he’s got to pay deference to Mab. If Mab gives him a command, he has to obey it. Mab’s too smart to throw him many commands, it’s much smarter to just let him do his thing. Because it’s this mysterious Christmas-y stuff anyway, cheer and goodwill, whatever. She supposes it’s good to have somebody like that for PR. That at times could be useful. It’s like, oh, so, Winter Court, whole season of death, evil, but then it’s like,  yeah, Christmas! Oh, wow, yeah, you’re right. It’s like the schools are trying to buy the tobacco company. **unintelligible** It’s something of the same thing. And besides which, if she doesn’t give him a bunch of orders and stuff, then basically, when she does go to him and say, “I need to know something”, that really, what can you do, this is our game of give-and-take. So, in a way, it’s not really a subservient relationship, Mab’s too smart for it to be that.