Apple did not officially make May 19th the 10th Anniversary of the Apple Stores, but things still seem to be happening this weekend.
Yesterday marked the 10th anniversary of the Apple Store, but Apple did not make any announcements. The rumors around the Apple Store 2.0 upgrade point to this weekend. The iPad 2 is the new POS system and Apple apparently already launched a new version of RetailMe. 9to5Mac has screenshots of the Apple Store retail software that now includes a cool Daily Newspaper for Apple staffers.
In the same report 9to5Mac publishes a tip they got from an Apple Store source. According to this tip Apple is installing the next version of OS X Lion on Display Macs in the Apple Store on Sunday. There is a huge secured download file waiting that is supposed to be opened on Sunday. If it really is an install image of OS X Lion is highly questionable.
OS X Lion will be the big topic at the WWDC 2011 starting in June 6th. It would surprise me if Apple is already showing it now in retails stores.