Nokia and Microsoft to announce an "alliance" tomorrow -- what? Update: Office on Nokia phones

We're not sure what to make of this, but we were just invited to a joint Microsoft / Nokia teleconference during which the two companies will announce an "alliance." Yeah, there are some pretty wild possibilities there -- Nokia going WinMo? Redmond going Symbian? The creation of MaeWinMo? -- but considering the featured speakers are Stephen Elop, president of Microsoft's business division, and Kai Öistämö, Nokia's EVP for devices, we're guessing the real announcement will be something more pedestrian, like native Exchange support on Symbian or possibly that upcoming Atom netbook running Windows 7. Otherwise, hell -- Nokia would be supporting three different mobile OSs, and that seems just a little too crazy, even for Espoo. We'll see -- it all goes down tomorrow at 11AM Eastern.

Update: This is probably unrelated, but Microsoft's Mac BU just called its own presser for Thursday, so if you're looking to spend the night weaving wild nonsensical conspiracy theories, we'd say all the pieces are in place.

Update 2: Told you it was nothing too out there -- the Wall Street Journal says Microsoft will announce it's working on a version of Office for Nokia phones. Anyone surprised? Didn't think so.