The pink-hued site, pottermore.com, simply shows that word in a logo that looks like a title, with Coming soon.... and Rowling's signature written beneath it.
Clicking on the owls on either side takes you to a YouTube page which reveals there are only 6 days and 13 hours until J.K. Rowling's announcement.
The owls are gathering, she writes there. Find out why soon.
A spokesperson for the author told The Guardian today, All we can say is that Pottermore is the name of J.K. Rowling's new project. It will be announced soon, and it is not a new book.
Update, 12:50pm: In a new Tweet, Bloomsbury Books says of the project, something brand new is on the way!