Very fun game!
I really had to think for some levels, but after...2 or 3 hours I think, I finished all the beginner's Maps :P
I agree with Burninbear, the game would go along faster if the brick-effect was really fast, but you should leave players with the option of either, because sometimes I'd move a little block, and half of the others would move.
Having the ability to choose speed/technique would make this awesome game...awesomer :P