The My Xbox section of Xbox.com and the Xbox forums will be off line for scheduled maintenance on Tuesday, August 4 from 0200 until 300 PT (0900–1000 GMT). During this hour, the forums will be in read-only mode and the My Xbox section of Xbox.com will be unavailable. In addition, many of the social features (your Inbox, retrieving messages, or viewing Zune Cards) of Zune.net will be unavailable. When the services return, there will be no new features. This is for scheduled maintenance only.
This does NOT affect Xbox LIVE, which will remain available during this time.