XBox 360 Design Review
A friend of mine (Alan Shen) helped develop the UI and pointed me to a good write-up of the process that went into creating the UI for the XBox 360. The article is at http://www.designinteract.com/features/xbox/
We don't own an XBox right now, or even a regular TV (just a PC running Windows XP Media Center Edition), but when the XBox 360 launches, we plan to get both a new TV and an XBox 360. I've seen it, and it's that cool.