In hindsight, the images used on findmakarov.com may have been a bit too obvious for a reveal that was still five days away.
An Activision spokesperson has told Joystiq that they have no plans to make an announcement about the future of the Call of Duty franchise and that any information claiming otherwise is a hoax:
There seems to be a great deal of speculation about the next Call of Duty project. Let me be clear that we are not revealing yet. Anything indicating otherwise is a hoax.
I still think this might be the real deal. Activision executives have constantly reinforced the belief that a new Call of Duty game is coming this Fall. They have to announce it eventually and the Game Developers Conference is a good place as any.