The tease is expensively and elaborately produced, including animation. This suggests Rowling will be announcing something important to Potter fans. When the new site appears it will be at Pottermore.com.
Many speculations have been aired about the new site. A summary of these appears here on Yahoo News courtesy of The Week.
My own speculation is the following: many best selling authors (e.g., Tom Clancy, W.E.B.Griffin, James Patterson) have taken on co-authors to expand their franchise. Rowling may be planning to do this, which would allow further elaboration of the wizarding world of Potter. Next week we will know.
