Update 2: The announcement has been made. Click here for full details. We hope your weren't expecting too much.

Word on the street (that is, Gamertag Radio) is that a major Xbox announcement is dropping tomorrow, set to coincide with the final round of the Pac-Man World Championship. Microsoft's Aaron Greenberg dropped the hint via an instant message session with GTR's Godfree. What the hell is this announcement about? We have no idea, only Greenberg's cryptic words, "we have a secret unveil for gamers around the world that I think will go down in video game history."

What in the world could it possibly be? Does it have anything to do with Ignition, Microsoft's new music initiative? We've contacted Microsoft to see if we can dig anything up, and we'll let you know as soon as we hear anything.

In the meantime, start speculating! What could it be?

Update 1
: We've learned from Aaron Greenberg that the announcement will take place tomorrow between 12:30 and 1:30 pm Eastern Time. And, before this gets out of hand, we've heard rumblings that this announcement won't be huge, but that it should be relatively cool nonetheless.

This article was originally published on Joystiq.

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