thanks for all the replies, and sorry i haven't been near my computer since i posted it originally.
i haven't had a whole lot of time to edit it yet, but i will say that there are two frames where no foot is touching the ground. but i'm not denying that he doesn't get any hang time, so here's a quick edit. let me know if i'm on the right track. also, there's a little bit of shake in the animation, like i didn't align everything properly when i leaned him over just a bit, and i'll get that fixed.
also, i giggled a little bit at the ninja comments. it's not really supposed to be ninja-y at all, to be honest. but i was liking the idea of a little bit more horizontal of a run. i think it's a good way to emphasize speed, i guess. here's some artwork:



EDIT: i went ahead and made it a little bit smoother, and i should work on stuff before i post it up here all willy nilly. i could have skipped like three steps:

i don't know. i played around with a couple different ways of changing the straight line left leg, but they all looked awkward. i think your edit makes him look like he has a freaky, deformed super knee. especially compared to the other knee.

hmm..i guess we'll just have to agree to disagree   

ok. that's it. done.  (tears of joy) a few minor edits. i'll probably be the only one who notices them, but oh well

I am loving the whole picture, except I would just think that on his left leg you would not be able to see his ankle? Or am I wrong there? That's just in contrast to the right leg, is all.

well, i made it so that the bottom of each pant leg lined up, and just drew in some ankles.  i wanted the cuffs to be a little high, so i guess i'm going to leave it like that.
anyway, thanks for all the help with this project, and now i'll go ahead and start on Tetsuo...