This information comes from Shigeru Miyamoto, on the latest episode of GameTrailers TV…http://www.nintendoeverything.com/?p=27321
“We’re in the middle of finalizing the game, the ideas that we’ve created, almost entirely new courses for Super Mario Galaxy 2. Of course we’ve added some new abilities for Mario. And the goal is to take the system and the gameplay of the original Super Mario Galaxy and turn it into something that’s a little more expanded and offers a great deal of challenge for people that enjoyed that first game.”
The original Super Mario Galaxy provides an incredibly entertaining experience, so following the game’s announcement, I was extremely happy. And if Galaxy 2 was to be more of the same (although I don’t think it will be), just being able to roam around in new levels would be fantastic.