Too easy in my opinion, up to level 30 and they all still feel the same 'medium' difficulty - makes it uninteresting. Also, you can see how to solve the puzzles straight away, maybe for next game make some that take a while to figure out?
I'm surprised that everyone things that beatmasher is hard. I found Music Relay really hard, it seems that you have to go slightly before the music beat.
Horrible game: Controls are very buggy and sometimes delay, the last level glitches for me
/spoiler the clone pauses when i throw the spike, then resets back to mirroring me /endspoiler
Also, who cares about portal promotions? why not use the forums, not the game comments