Hobbit RPG? DC Superhero RPG? All this speculation drives me crazy.
In the end, Obsidian is probably not involved in any of these anyways....
While I agree that it isn't likely, 'superhero from Warner's DC Comics' would potentially fit with a number of 'leading animation franchise' s quite well.
It would fit it perfectly. If you look at success WB has had with Batman: Arkham Asylum and the upcoming Arkham City, it really wouldn't surprise me that they wanted to launch somewhat similar title with some other superhero of theirs.
But while it would fit the clues, it's more than likely WB has one of their own internal teams working on such project.