Just after announcing "Water" the new add-on for LBP, today it looks like Media Molecule is testing the waters... in english they announced, via Facebook, that they will be hosting a closed beta for the upcoming add-on.
And incase you didn't know, "Water" adds a ton of new gameplay, with new levels made by the team and a whole new game physics mechanic the element of water.
You can watch the new trailer for the add-on here;
and click here, the beta site, to sign up. So, good luck.