Downloaded the demo and I must say I am impressed. The demo at least is as good as the hype.
Although the game play is fairly easy to get used to, the in game options are endless. You can switch from being a batter to a runner, and dictate what kind of hit you want the computer to take. There is even a part of the game were you can argue a call with the umps. If you argue successfully you get morale/motivation points for your team. If not you lose your manager and or a player.
It seems like 2K thought of every little detail in the game. One of the things I like is that you have to get your relief pitchers in the bullpen to warm up before you get them in the game, but at the same time if you leave them in there too long they start getting tired. Another detail of the game is that your pitcher can get rattled (your pitches go all over the place). You have the ability to send your manager on the mount to calm him down.
Graphics are amazing and very detailed. Just like the 2k Basketball series you can tell who the players on the field are, by player trademark moves, etc.
The only bad side to the game (That I could find in the demo) is with all the added features, a 9 innings game could take forever (as if baseball wasnt long enough).
I am really looking forward to running a franny season.
My demo rating for the 360 is a 9/10