Well, I don't know if you guys knew this already or not, but for those who didn't know, it might be pretty helpful.
Anyways, the whole point of this post is because Photoshop CS 4 Extended Edition supports video, therefore you can actually import any video to photoshop and apply filters or effects to it using photoshop. Now, I really haven't tried it yet, but I am guessing the quality should not be affected at the time to export the movie.
I think this is pretty cool since it gives you the chance of applying amazing filters and effects that most probably are not available in Video Editing software.
Here's a segment (no audio available) on how to do a small change with colors. I am also adding a link to the full video where you can hear what the guy is stalking during this tutorial. The video is at high speed, but is just so you see how you can affect the video, in this case the color, with Photoshop.
Tutorial - Episode 223
Photoshop User TV