It's not a launch in the sense that it's going on sale tomorrow. It's more of a press conference and demonstration of what they're developing for the new console that will likely be released later in the year.
We'll probably see the actual machine, surely they won't make the same mistake Nintendo made when revealing the WIIU and the confusion the followed because they never actually made the point of saying until their press conference was over, that it was a new console and not just a new controller for the Wii.
Well also probably see a new controller, though I hope they don't deviate from the current controller much. I'd be entirely fine if they just stuck with the current controller, though I doubt they'll do that since selling controllers makes a lot of money.
We'll also probably see a variety of game trailers and a hand full of demos, ranging from the usual Microsoft exclusive titles. Though I'm hoping that they've got a few new IP's in their back pocket as well. Microsoft could stand to use a few more exclusive titles.
And of course, whatever new changes are being planned for Xbox Live will certainly play a large part in their presentation. This includes not only the expansion of multiplayer gaming, but also their continued move towards being a hub for home entertainment. I wouldn't be surprised at all, if Microsoft has locked up some exclusive deals for premium content, much in the same way they led the way with Netflix. Microsoft has deep pockets and has a long track record of throwing money at whoever will take it in order to lock in exclusive deals to make sure the Xbox gets new content first.
Needless to say, I'm very interested to see what happens tomorrow and I'll definitely be watching the live stream. I'll probably watch on IGN.