I placed my order for a 591 ($349.99) and a set of Polk Audio RTi4's ($149.99) off Amazon this morning. Free shipping.
I won't be running a sub or center for awhile, and will be using some Sony HTIB for the rears (temporarily). I'm stoked!
Upon reading this thread I realize I could have gotten an older model since it will be years before I go 3D, but that's OK. I had to use Amazon (had gift cards) and their selection was kind of spotty.
My only source component is the 360, which I use for movies, games, and Netflix instant. I get OTA HD to my TV's antenna input.
I do have one question: what is the best way to play an iPod through the 591? The dock is expensive. That's the way I usually play music through my AVRs since I don't own a CDP nor have an HTPC. My Sony HTIB came with a dock which was awesome. Any ideas?