Well, I don't have one myself, but I still have a few tips:
- The XBOX is often a target of ports from the PC due to the very similar internal architecture. When considering a title, look to see whether it's on PC first - the PC version will often be better (ESPECIALLY with Valve games)
- Make sure you get a *new* X360, and make sure it was manufactured within the past half year or so. All the others have hardware problems, and the used marketplace for 360s is flooded with banned consoles that can't go online to play multiplayer or recieve updates.
- Index of Xbox 360 Game Reviews by Score
I'm tempted to get a 360 because of the XNA development kit ability, and
Bayonetta. I probably won't, though - it's too much money when I have yet to finish so many of my other games.