Whoa, what's this? Apple just updated its homepage with a new splash screen teasing an "exciting announcement from iTunes" at 10AM ET tomorrow, saying that "Tomorrow is just another day. That you'll never forget." All streaming subscription service based out of that North Carolina data center? More video content in the store? Apps for the Apple TV with the iOS 4.2 update? The Beatles? Whatever it is, we're digging for more, and we'll let you know as soon as we find out.