Positives:
+Great gameplay, seriously - very simple concept, yet intensely addictive
+Excellent music
+Has a pause feature! Intensely helpful - too many games like this don't, and it's always so frustrating to lose a good streak because I got called away.
+Cute graphics
+Smooth movement
Negatives:
-No mute option. I like the music but it would be nice to be able to turn it off if it starts to wear
-Waterfall effects like woah.
-Pause button appears to be click-only, and the time it takes to move the cursor over to pause can easily kill me during even the more moderate pace.
-What's up with the random flashy rainbow lines I keep running across? They're distracting, seem to serve no purpose, and their color changing effect annoys me.
All in all, intensely addictive. I can't seem to stop playing it even as it makes me motion sick. Wonderful work.