It seems like almost all of my friends have read this already, and I can see why. I really enjoyed it. Sure, none of the concepts in American Gods are really original, but it's well-executed. Even with my barely passable knowledge of various religions and mythologies, it was fun to figure out who might be a god and which god they were.
I've read a decent number of Gaiman's books by now, and this is my favorite so far. It's not exactly fast-paced, but the plot rolled right along like an old Winnebago on Route 66, with enough action sprinkled in to keep my attention. The twists were plentiful and of the best kind --the ones you don't seem coming, but they make perfect sense in retrospect. There were a few slow parts -- the dream sequences, in particular, became a little tedious after a while -- and the connection between some of the "Coming to America" sections and the main storyline wasn't always clear. These faults were really minor, though, and I think the good far outweighed the bad.
If nothing else, American Gods definitely piqued my interest in learning more about mythology. This might be one to re-read in a few years - I think it might be even more enjoyable the second time around.