Take a quick peek at Apple’s website and you won’t find the usual product offerings and announcements. Instead, emblazoned across Apple.com is a giant teaser that reads:

"Tomorrow is just another day. That you'll never forget. Check back here tomorrow for an exciting announcement from iTunes.”

Scheduled for 10 a.m. Eastern, 7 a.m. Pacific, the pre-release announcement has set tongues wagging. John Biggs over at technology blog TechCrunch writes: “I personally haven’t heard much out of Cupertino this week but we’ll do a little digging to figure out what’s going on here.”

Possibilities include the long-awaited approval by the surviving members of the Beatles to allow its catalog to be sold in Tunes. Others are speculating that it could be news of an iPad software update. Mashable hints that it might be a new music subscription service that would complement its existing pay-per-download service. Or perhaps the launch of a Web-based iTunes where music lovers’ music would be stored in the cloud on Apple’s servers and streamed to a variety of Internet-connected devices.

Yet All Things Digital’s Peter Kafka says industry watchers shouldn’t count on music subscriptions or streaming from Apple. Kafka reveals: “The music industry sources I’ve talked to so far today don’t know of any new deals between Apple and the big music labels. So that would rule out a new subscription service, which would definitely require a new rights deal. And that also makes it very unlikely that Apple does the next best thing: Letting users upload their iTunes catalog to the cloud, and letting them access it anywhere they want.”

So what can we expect? Maybe longer preview times. After all, Apple has already announced plans to extend iTunes’ preview time for a song to 90 seconds, or triple the current limit. Recently, MacRumors landed a copy of the letter Apple is sending out to music labels stating that any song longer than 150 seconds will get the 90-second preview. Any song shorter than that will keep the 30-second preview

Then again, we could just wait until tomorrow morning to find out.