Wouldn't it be fun to be able to travel around the US, taking the comments on this thread and making up your own mind?
When Houston's restaurants first decided to offer pizza on their menu, one of the executive chefs actually traveled around Italy searching for just the right pie to re-create in their restaurants. Not a bad gig, eh?
Anyay, living in PHX, I am a long way from the renound Pizza Dynasties that exist in Chicago and New York. But here in the Southwest, for my money one of the best has to be Oregano's. Sure it's a chain, albiet a small but growing one. The places are always packed, but for the simple reason that they do a mean pie, Chicago style.
If you're looking for a tasty, thin, wood-fired pizza with no wait, try Goldie's in Scottsdale. The place is a sports bar, but they take their pizza very seriously. (They also own Zipp's, with 3 or 4 of them in the area, their Black and Blue burger rocks, but that is for another thread.)
For something a little more upscale in a really neat setting, Pizzaria Bianco in downtown PHX is top notch. The place is in an old house and, while you are waiting for a table you can walk next door where they have another old house. Sit on the porch or inside in one of the rooms and have a drink until your name is called.