Game is fun but a couple things I noticed.
1) The controls feel a bit wonky to me. It seems odd to have to hold the spacebar button to not move blocks and then let it go to move blocks. I feel like this should be the other way around. You move around freely, then have to hold spacebar to move the block.
2) It would be nice if you could access some sort of sound controls from within the game besides that start screen.
3) There is a lot of empty black space on the screen when playing. Could a nice background be made? or perhaps have the blackground flash colors when you make matches... something
4) The person who commented above me (Mechie) makes a good observation about the replay-ability. An endless mode would be great.
5) I noticed this is only available for winodws an osX? are there plans to release a mobile version? I would find this much more entertaining on my phone as a time killer.
Overall fun game thought. Nice job.