"Tomorrow is just another day. That you'll never forget." It then says, "Check back here tomorrow for an exciting announcement from iTunes."
Those are the words you are greeted with upon navigating to Apple's homepage. Nothing else is mentioned, and the teaser does not navigate to a new page. We know that iOS 4.2 is expected to land anytime this month, but it isn't clear whether or not this relates directly to that. It's very possible that the announcement takes iTunes much further than it is right now. Either way, we should be finding out for sure around 7am PST, or 10am eastern. We will keep a lookout, and let you know as soon as something comes up.