I like the core of the game.
I thought it was alright, but after 1068 boxes I simply quit it out of boredom. I think the idea is good, nothing too new or original, but it works. My advice, spend some more time on it, add in something you need to collect, add some goal to it, have a menu screen, going straight into a game never works. People LOVE leaderboards for this type of stuff. Just spend a lot of time adding onto it. Maybe have different levels, such as holes you actually need to go through, that'd be much more challenging, get it to speed up, have bigger nasties come at you, as a story line, I'm sure a random story about a stranded red blood cell trying to find it's way back into the mainstreem of your veins would be a brilliant heart-warming story the whole family will love!
I am a sucker for these types of games, although they are not really new, or innovative, but they work. So really, just add to it, and I think it will be a good game.
PS. It's not really that close to 3D, lol.