You likely have the Kodak Zi8. Did you cut the movie in iMovie? Sometimes when you compress the files for vimeo/you tube it will make it choppy. Other thing I learned from experience is that when Vimeo processes the video's that are in HD, it sometimes screws things up. YouTube does not generally have that problem. Nice video though!
#1 Key witht he Zi8 is to have some kind of steadycam device. With one, your videos can be spot on.
#2 Tip - shoot in 720p at 60fps, not 1080p. 1080p records at under 30fps, so if you try to speed up / slow down the video in edit, it will make it all choppy. You wont have this problem at 60fps, and the difference between 1080p and 720p when you compress for Vimeo/YouTube is not really noticeable.