Hmm.
This looks a lot like a game some folks over at albinoblacksheep coded: http://www.albinoblacksheep.com/games /run . But I'm not accusing you of anything, since the concept of "holes in the floor" has been used/seen before. However, I do think that this version is a bit.. dysfunctional in some aspects. Here's why.
First off, this does not use a 3D engine/simulator. Flash is very capable of running 3D-like graphics, even in older versions, it just takes a bit of trickery and change of perspective.
Secondly, that's what this game needs. A better sense of perspective. You've got it on a 2-dimensional level, but it's still hard to tell whether I'm landing on a solid square or a blue hole of water.
If you look at the "Run" example I just linked to, you'll see that there is, in fact, a sense of perspective, because where the character moves, the environment follows. When the character falls in a hole, you see him fall through the running field.
Now, the good stuff. I like the music, and how it's consistent in all of your different versions of this game. The controls are simple and smooth; always hard to accomplish in a simple game like this. Maybe with a few more plays, I'll get used to it; but this is just how I personally see what needs to be improved on.