"The owls are gathering... Find out why soon." That's the tease on YouTube from Harry Potter author J.K. Rowling, on a webpage that features a clock ticking down the seconds until Thursday, June 23. With the final movie in the mega-popular Harry Potter series due out next month, Rowling has launched a "mysterious" new website called Pottermore, and is teasing it on YouTube. Rowling's representatives have said the site is not about " a new book" and "not directly related" to the upcoming film. So what's it all about? Here, seven theories:

1. A Harry Potter encyclopedia
This could be "some kind of a reference site," says Linda Holmes at NPR. "Rowling has mentioned more than once" that she'd like to put out "a comprehensive reference tome of the wizarding world of Hogwarts," says Stubby the Rocket at Tor.com. Pottermore could be an announcement about that encyclopedia — or it could actually be that encyclopedia, like "a wiki-style information portal."

2. A spin-off site for secondary characters
This site "could be an online universe for all the other characters in the Potter world," says Melissa Bell in The Washington Post. Rowling has said that "she created backstories for most of the beloved side characters, much of which were never revealed in the novels." And Pottermore "sounds as if it could be a place to host those extra stories."

3. A video game
Pottermore might stand for "Potter Multiplayer Online Role-Playing Experience." A massively multiplayer online role-playing game (or MMORPG in gamerspeak) set in the wizarding world "would be such a large amount of awesomeness it wouldn't even fit in Hermione's handbag," says Keith Staskiewicz at Entertainment Weekly.

4. A social network for Potter fans
"The idea of a PotterBook or HarrySpace does make some sense," says Leslie Gornstein at E! Online. And the teaser site and YouTube page both feature owls, which "are the chosen method of long-distance communication in the wizarding community."

5. Potter e-books
The release of the Potter series as electronic books "has been a long time coming," says Staskiewicz at Entertainment Weekly. Though this kind of hype, and a trademarked new name "only to announce e-books doesn't seem like Rowling's style," says Stubby. Still, her PR person declined to comment when asked about the possibility. "So maybe that's all it is."

6. A new theme park
Could this be about a new Potter park coming to the U.K.? A place "where fans can unite and bask in butterbeer and magical merriment for the rest of their days?" wonders Wigler at MTV Movies. There's already one in Orlando, so "a second park doesn't seem all that likely," says Gornstein at E! Online.

7. A real wizarding school
"Come on: You know magic is real," says Wigler. So does Rowling. "It was only a matter of time before she pulled the curtain back all the way and started her very own Hogwarts. Start prepping those admissions packets now, wizards-in-training!"