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Alert: Fall update Live ID bug
If you are particularly attached to your Community User Level or forum icons please DON’T change your Live ID until we deploy a fix. It should only be a few days, and we apologize for the inconvenience. We will let you know as soon as it is safe to change your Live ID and keep all your forum goodness.
If this is not an issue for you, please go ahead and change your Windows Live ID if that is what you wish to do.
Posted on http://forums.xbox.com/17102451/ShowPost.aspx by the Xbox Live Support Team