I love long, epic books in which I can become enveloped, but even my favorite ridiculously lengthy books took me awhile to get through. I read this 800 page monster in exactly three weeks (and that was with a lot of other things happening to divide my attention). That clearly says a lot. I was tempted to go with four stars because this doesn't really END, since it's the beginning of a larger story, but I decided to go with how ridiculously riveted I was and go for five.
I had heard a lot of raving about Martin over the last few years, and now I pretty much have to put myself in that possibly over-praising camp, because this was real damn good. It manages to be huge and epic while being immensely character-driven at the same time, which really is what I want from most books. It manages to make dragons and snow-zombies feel realistic (largely because they only barely show up in this first installment) and shows most everyone as three-dimensional (with a few exceptions). This last quality became especially apparent when my favorite character (favorite by far) who is, ostensibly, a villain, maybe, spent a good chunk of the book a prisoner to a character who, again ostensibly, would be seen as one of the "good guys"... whatever the hell that means. Just the number of qualifiers in that last sentence should give you an idea of how nuanced the characters and alignments are.
Lastly, and perhaps most importantly, the book is pretty much all setup without ever really feeling like setup (except, maybe, in the last chapter or two). Instead of spinning its wheels uselessly to kill time until we get to where we need to be, things are constantly happening and the status quo is always, always fluid. Even though I had some vague ideas of what the series' overall story might be, I was pretty oblivious as the various subplots weaved in and out of each other, playing out stories that could, themselves, have made their own book.
So yes, I liked it. Now I have to fight the urge to read the next ones (which are sitting on my shelf) because I certainly don't want to get used to reading them one right after the other and then suddenly be forced to wait years and years for the next.