I haven't explored a whole lot yet - haven't ventured online, for example. However, I did manage to get two games in - one normal and one in coach mode. I'm digging coach mode, honestly, because it's more of a puzzle game about picking plays and outsmarting the opposition, than the detailed control of players required in normal gameplay. (I'm not sure when that feature was added, since I haven't bought a copy since 2004, but it's nice.)
This game is basically a work of art in HD. The stadium is nearly perfect, including the touchdown lounge house thing and the foothills being in the right spot and the right shapes. The shade of blue that the turf was rendered actually reminds me of the stuff they took out last year - kinda shiny looking. It was very nice that they made a point of getting everyone's "traditions" correct, down to what the stadium announcers are saying in the background.
I'm rather excited to start playing online tomorrow night, actually. If anybody else is up for it, we should discuss in the comments. I'd rather play with you guys than the usual xbox live crowd.
One of the most amusing features is the ability to take video of highlights and upload them to the web. The following video made me far too excited. TAKE THAT, PRYOR!!