Apparently J. K. Rowling has announced the name of the seventh book on her official website.
Unfortunately, the Firefox Popup Blocker (along with the Flashblock extension) conspired to prevent access to the site, because the stupid thing is (apparently) in a Flash popup. Hmm: Ctrl-W. Make the bad site go away.
Fortunately you don't need to actually visit the site, since the title has been posted to Slashdot (based on a post in an emulation forum, of course): it's (apparently) Harry Potter and the Deathly Hallows.
Spoiler: Harry dies at the end. He's the last Horcrux, or however that's spelled.
(Well, maybe not. I'd hope not because that's just way too obvious an ending.)