Well... nothing overly useful for me.
Games On Demand is a total joke. Good concept, horrible execution. They're charging MORE for the download than the cost of an actual copy in most cases.
The avatar store is a complete joke. Maybe it's just me, but the point of buying clothing and gear for your avatar is completely asinine. The thought of somebody spending msp (cause that equals money) just... irks me. I want to call those people morons, but... hey, Halo fans are Halo fans right?
Game ratings are okay I guess. That won't sway me into getting something, but it's still good to voice your opinion. 2* rating for Halo 3 = good times.
The only major update that I find of use, is the ability to play games from the Achievement browser.
One day, they'll give me the ability to get rid of that damn gradient sphere that covers more than half of my wallpaper... yea right