Great!
I gave it a 7 based on the success of the game against what it was trying to acheive. I think 7 is high in comparison to other, more ambitious games. On the other hand, this was brilliant for what it was. The graphics did the job and the music suited the action. I really enjoyed playing this, and that's the most important thing. My only suggestion would be to perhaps consider making the boulders move at different speeds, increasing the chances of a combo if your timing is right. Good work!