I read and liked it, though it's the first book I've read by the guy so I can't really compare it to the others.
It's not really about anyone being gods, per se... there are gods, but they're in people's imaginations, or something... I have to read the sequel to get what's going on in that front. It's a very "science meets religion" book, kind of like "Angels and Demons" except "Ilium" is good.
"Ilium" is pretty much divided into three seperate storylines that don't start intersecting until close to the end: a hard sci-fi story (cyborgs living in the Jovian system), a utopia-dystopia story (GM humans slowly devolving) and a spy novel (a dead guy that the "gods" brought back to study the Trojan war).
It's a good book with some interesting plot twists and ideas from the author, so I'd read it if i were you.