I'd like to think that I am a completely grown man and completely immune to the Harry Potter franchise's mysterious draw, but dammit, that music starts up and I want to start waving my wand around and...not finishing that thought.
I'm really not sure about another Lego game.
There really is little innovation between games... so little that if you've played a Lego game before, and have a passing knowledge of the films, you can pretty much guess what the game's gonna be.
In other words, take the shooty characters from previous games, add force powers (just add a magic wand to the jedi animations and you're there) give it an isometric viewpoint and paint it with Harry Potter. Et Voilà!
They really should try something a little different this time...
Plus Dumbledore didn't deliver Baby-Harry.