Update: Things are running a little late. It should be starting around 10:30 a.m. PST.
YouTube is holding a press conference at 10 a.m. PST Thursday and we'll be there live with photos and text updates of whatever it is.
Details are scarce at the moment, but we know for sure it won't be related to mobile phones or movies. That opens up the door for a number of things including new Test Tube features, , and that which was rumored to be coming out sometime in 2008.
As with some of our other live blogs, if you want to get a reminder before it starts, just use the sign-up post below. In the meantime, if you're itching for something fun to look at, you canCNET got last week at YouTube's San Bruno, Calif., headquarters.