Whoever said the console Venn diagram line, *claps*.
If you want my opinion, I see the 360 and the PC merging down the line; the differences between the platforms have become very small: 360 controllers can be used very easily on PCs. It's theoretically possible to get a M/KB working on a 360 (the implementation quality is questionable). 360s and PCs (and PS3s) use hard drives to game now more than ever. Games for Windows (if they would get their shit together) would make the front-end difference even more negligible. XBLA and Steam aren't all that different in execution.
Personally, I'd love to sync up a 360 Elite (because it looks badass) and my PC [which already is badass =) ] at home to an epic sound system and HDTV so I can play PC games, 360 games, watch videos, surf the Internet, do work, play music, communicate, and watch TV all from that center. Ultimate media center, here I come!