I dunno about that, either. They only recently added a lot of 'Shamu' themed rides to that area. The 'Shamu Express' kiddie coaster was added in 2006 and I recently noticed a whole lot of sea-themed stuff there that I hadn't before... like that carousel and such.
I really hope they don't go that route, laying a flimsy re-theme over it just because A-B holds the rights to the Sesame Street characters. After all, it's SEA World... I can only hope they'll stick with their roots.