They do maintain legal rights to the game itself, the concept behind the game, its art assets, etc. Naturally, it is of course illegal to reproduce the game. Depending on how you market (or don't market) any recreation you might attempt though, you might avoid Disney's lawyers. For example, our single player recreation over at vmkrevisited.com seems to be surviving without issue.
As an aside, welcome to DisneyMMO.com! We're not too active on the forums for the moment (the site is in a pre-launch phase), but do check us out in the chat sometime over at http://disneymmo.com/chat. There's usually a good crowd in there during evening hours.