Thanks to
Game Informer Magazine, we now know the locations Ezio will haunt in the next entry of the now practically annual series.
They are Masyaf (the Assassin's fortress city from the original game), Constantinople ("center" of the world, capital of the Ottoman Empire, and broken up into four districts: Constantin, Beyazid, Imperial, and Galata), Cappadocia (underground Templar stronghold), and Rhodes (of "Colossus of" fame - multiplayer only).
Assassin's Creed: Revelation is set for release this holiday season.