The 1.02 update is out, changes here.
This was suppose to be a medium update which fixes a lot of problems. Unfortunately a bug in the public session select screen (a new feature) may crash the game. It's advised that you invite friends to a private game in the meantime.
While we do have a fix for it, we can't update the game due to XBLIG restrictions. Please be patient, the update should be available by late next week.