I figure I may as well post since my name is in the thread.
This is what I figure an Xbox 360 released in 2012 will look like.
Performance (Whatever they want that uses about between 75-125W of power) Speculation on exactly what will be in it has been done to death and really it doesn't matter. This gen pushed heat output too far so I can see them scaling it back considerably. As a general idea an 8800gt produced on a 55nm process uses about 100W of power currently so probably only 4x the compute power of the current generation of consoles. I would suggest efficiency would be quite important in the next generation, having general purpose silicon would help them there so I would expect a unified CPU/GPU architecture. Larrabee could be perfect in that role, especially mated with Sandy Bridge because they both have a ring bus.
Storage/Devices, it really depends on what floats their boat at the time. SSDs, HDDs, Blu Ray and Flash game media all have compelling advantages and disadvantages. It doesn't matter how the game gets to you really or how its stored when it gets there.
Memory: Probably 4x 4gbit ram chips, if you take into account two process shrinks for memory. So that'd yield about 2gb of total ram. They'd want to simplify the system and thats one of the ways to do it.
Interface: They have the Xbox 360 with standard controls, so they won't have a problem trying something new. Im predicting a two piece symetrical controller with motion, pointing and 3d position sensitivity for each.
Tease.
