According to the site, the short theatrical 3d re-release will come out August 12th in New Zealand (where the trailer originated) which would suggest the rest of the world would get it around the same time. This ties in with other Disney releases in the works such as Ratatouille that we broke the news on in a recent interview.
Beauty and the Beast is released on Blu Ray in the UK, 1st November 2010 and you can pre-order it here.
Check out the new trailer below: