Ok, let's see.
What could it be?
1) Smash Broadcast's announcement: if we need to base it on the 16th's date, an announcement on 7th sounds way too early. If it's indeed on that day, it would be announced on December 9th, 7 days before it happens. It's also possible that the broadcast happens earlier, and Cloud (+ whoever else is there) is realeased a few days after the broadcast. A live stream on December 14th could be announced on December 7th, just to say.
2) Minecraft Wii U Edition: already rated by PEGI (page then removed, but it's not a fake: things don't get rated without consent/randomly), it could be the time for he announcement
3) Some major indie game? Well, it's Damon. Nindie love all over our souls. Seriously, though, it could be a possibility.
4) A brand new Humble Nindie Bundle could happen, since the first one was successful. When are HB usually announced though? IIRC, it was on Tuesdays, but I could be wrong. Or maybe, even if Tuesday is the usual announcement day, there's something different/special, so the announcement is earlier.
I suppose this covers all the possibilities we can predict.