Microsoft's goal with the 360 and even more so with the 720 is to take over your living room.
Microsoft will do it this way:
1) Focus on NUI (Natural User Interface) - Kinect 2.0 in a big way. Microsoft wants to remove the barrier for interacting with their systems, and Kinect has already taken great strides in that direction. They'll improve on it for the 720, possibly bringing in additional tech.
2) Social integration - Everything you do is something that should be a natural extension of the 720, and Microsoft have already made great strides in this area with the 360, but if WP7 is anything to go by, they have more to come.
3) A unified experience - Your Xbox Live, Zune, Windows Live, Skype and every other relevant Microsoft service will come built into the 720, and the experience will be as close as possible across all of Microsoft's platforms. Expect great tie-in with Windows 8, possibly some SkyDrive integration and others.
4) Cross device connectivity - Your 720 will be connecting to your Windows systems in lots of different ways. We already saw the demo with the ricochet stuff for Kinect connected to WP7. As Microsoft controls the hardware (to some degree) on WP7 and W8 tablets, expect this connectivity to be emphasized. Don't be surprised to see the 720 running W8 apps.
I'm sure there's a bunch of other stuff in there, but I think these will be the essential bits. 







