J.K. Rowling made a highly anticipated announcement about the Harry Potter franchise today. Here are details as they emerge. 10:50 a.m.: Pottermore or Potterbore? There's an almost universal story among Tolkien lovers of how, after finishing the final book in the trilogy and mourning that it was over, they discovered on the backpage that there was a fourth book. It bore the mysterious title The Silmarillion, and you begged your mom to drive you to the bookstore that night to go buy it. Only to discover that it's unreadable. It's a dry history of a completely different era in the Lord of the Rings mythology with no apparent tie to the main story. I would wager the median page at which one gives up is 30. This was my first thought when I read that J.K. Rowling was releasing 18,000 words of extramaterial about the Harry Potter series \u2014 things like Professor McGonagall's affair with a Muggle or the 10 things you didn't know about House Hufflepuff. Rowling's world is far more vibrant and charming than Tolkien's, but she was also far more economical. She certainly wrote more pages, but there weren't a lot of details about the wizarding world that didn't inch her magnificent mystery forward \u2014 even if you didn't understand why until three books later. I hope I'm wrong, but if what we're getting is cutting room floor material, or even new self-contained stories, I worry that the new information will lack that which made every detail of the books so riveting: that the fact that a rat is missing a finger in book one turns out to be the key to the mystery in book three. 10:25 a.m.: TIME's Sonia van Gilder Cooke has a more detailed description of the experience. "Users start out at Privet Drive, where they can explore Harry's cupboard under the stairs (replete with scampering spiders) before moving on to Platform 9 ¾, the Hogwarts Express, Diagon Alley and Gringotts," she reports. But "Pottermore isn't a game: it's a series of illustrated environments." 7:45 a.m.: A few more details. The Telegraph says users will chose a name, and then play interactive games on the site to choose a wand and get shorted into one of Hogwarts' four houses \u2014 the first two rites of passage for new wizards in the books. But it's still not clear what you do on Pottermore. Is it a reading experience or gaming experience, in which you unlock content as you cast spells and so forth? More than anything, this sounds like a digital theme park devoted to Harry Potter. And there's a giant stuffed Blast-Ended Skrewt with my name on it. 7:25 a.m.: Alright, this turned out to be the world's most pathetic live-blog. But here's what we know about Pottermore, based on Rowling's announcement and some embargoed news stories: - The site will have a lot of new material about the Potter universe that Rowling said she has been "hoarding." - Users (or is it players?) will be able to upload their own drawings and comments. - You won't be able to participate until October, but a lucky few will get access on July 31st, Harry's birthday. - The 18,000 words of extra content include info on wand wood, the other three houses at Hogwarts besides Harry's, and backstories for some of the secondary characters.* 7:15 a.m.: The live webcast of the announcement is hopelessly overrun, but the Pottermore website has the prerecorded video. The immediate news is that the Harry Potter books will be released as eBooks as part of the new website, which will involve fan submissions of some kind. Details soon. 6:14 a.m., June, 23: I swear one of those owls on the countdown page just winked at me. 45 minutes to go. Correction, June 23, 2011 : The original version of this post said that Pottermore would have 18,000 pages of new content. Follow Brow Beat on Twitter. For more culture coverage, like Slate Culture on Facebook.