User blog comment:Dopp/Communicate Easily with Message Wall/@comment-1903385-20111011211059/@comment-1656630-20111011215622

Currently, the notifications only work for the wiki you're on, and you get a regular "you have messages" bubble when you're on a different wiki, to tell you to come back to the wiki. This may be expanded in the future, though, if we find a strong need for global notifications for working on multiple wikis.