How much traffic do these sites usually drive (per impression, rating, etc)? I'm interested in writing an Ajax/Php script for this.

I've also seen watermarking that flashes in a few seconds in or so, and maybe towards the end would be good too. I'll look up video encoding and write a script to do it. I figure there are linux libraries or command line apps that will do the job.

I've got a pretty good idea for monetizing this traffic as well, and a great content source that's legit.