Another neat thing about the Xbox is that everyone can register for a gamertag that tracks their playing statistics. This is then accessible on the web, much like Battle.net accounts, for example here is my gamercard. It looks like there is a public API to these statistics (or maybe it’s just a lot of screen scrapping), because there are services that crunch your stats and produce graphics. Like MyGamerCard.net which allows you to make forum signatures from your gamercard:
Another neat idea is 360voice which gives your Xbox 360 a “voice”. Basically a blog that talks about what you’ve been playing, and what you’ve been achieving. Here’s my Xbox’s voice (which is also part of my LifeFeed). Originally I had my privacy settings set such that only my friends could access my play statistics, so my “voice” was really dumb. But now that’s rectified and more informative.