An inside source at Microsoft informed us that Microsoft is currently finishing off one huge update for the Xbox 360 that is going to put an end to all the common problems in both games and the system itself. It will contain fixes for all currently known lockups in games, missing or impossible to get achievements and a bunch of new functionality in the Dashboard.
The update package will be released as soon as possible via a central dashboard update. The webcam accessory is going to be released simultaneously or slightly after, because one of the Dashboard modifications is going to be camera support. Whether background downloading is another is not known yet.
All information above is subject to change until official confirmation. We will be keeping you informed of any updates ofcourse.