Read the books before the show, and in a way I feel a little sorry for those who are approaching from the other direction.
In certain cases, I kind of prefer "approaching from the other direction." As we've seen in this case, reading the book(s) first and then seeing a movie/TV adaptation of that world almost always leads to some level of disappointment. It's the nature of the beast.
However, if you're exposed to the video version first and - like me - are intrigued enough to check out the source material, you are given the key to unlock a door that opens onto a richer, more detailed world that fleshes out what you've already been enjoying onscreen. (And, when I've skimmed bits of SF, I tend to visualize Paul and hear his voice; which tells me that, for me at least, Paul is going a good job of maintaining the spirit of Harry.)
I'm in the middle of another book, so I haven't had a chance to read my copy of
Storm Front, but I went to Borders last night while running errands and picked up a copy of
Fool Moon anyway, because I've been that impressed with the show and what I've skimmed of SF. I couldn't resist - I started reading FM in the car before I drove away, and I got sucked in, reading the first 12 pages in one
whoosh before I realized I'd done it.
I'm beginning to understand the wicked fast reading times I've seen quoted on this board.