The Communications committee is working on coordinating the use of sitewide notices for Wikimedia projects. This is needed for the upcoming fundraiser, as well as other potential announcements relevant to all projects, such as Wikimania or technical issues like single login.
It's anticipated that we will use a bot to help update these messages, which due to the nature of the pages being edited will need to have universal sysop privileges. Rest assured that we won't be using it for other sysop functions. Naturally, with all of these messages we will need help with translation, ideally before they are distributed but also after if necessary. Please let your projects know in case they have any questions.
--Michael Snow Chair, Wikimedia Communications Committee