Xbox LIVE Indie Games Submission pipeline on App Hub is now open for Xbox 360 games made using XNA Game Studio 4.0. You can submit your XNA Game Studio 4.0 games for Xbox 360 to the Peer Review process on App Hub right away.
"For XNA GS 3.1 games still in development, you've a limited window of 90 days - starting from today - to continue to submit games made in XNA GS3.1. XNA GS3.1 games submitted during this time will continue to work after the 90-day period.
The last day to submit XNA GS 3.1 Games: Monday, Feb '7th, 2011 at 11:59 PM PST
Today's update also means changes to XNA Game Studio Connect, which you can use for deploying and debugging your XNA Game Studio projects in progress. Read on to find out how these changes may affect you.
If you've a XNA GS 3.0 or 3.1 game currently on Xbox LIVE Indie Games, it'll continue to work. This release doesn't affect the ability to purchase or play any game currently on Xbox LIVE Indie Games."
More Info: App Hub