I have a 2008 and I find the rear cargo capacity and space pretty generous compared to others that I have driven (Infinity, Lexus, etc.) in the same class. The rear seats are a 60/40 split and they both fold down forward almost flat. One thing about the trunk is that though it's spacious, there is a lip or edge (for lack of a better word) around the bottom and sides that limits the size of what you can actually load from the rear. A lot of other cars have this same limitation.
I have loaded a mountain bike in there (minus the front wheel) easily and a 32-inch LCD TV (with box) separately but not much bigger. I don't really transport much.
The front seats both fold back as far as they can go until they hit the rear seats. I have slept in the passenger seat on a road trip and it was fairly comfy and wide as long as you have some kind of pillow for your head. Plenty of leg room too.
I don't have a roof or trunk-mount rack, only a rear hitch bike rack rack which doesn't get in the way at all in it's normal position. It can fold back if needed. One problem with a rear hitch-mount rack is that it can scrape going in or out of some driveways that are angled. I had mine modified and it isn't a problem even with extremely angled driveways. And it doesn't interfere with the trunk at all. I hope that helps.
