stevemassart - 3:04 pm on May 5, 2010 (gmt 0)
you don't have to include both, just one or the other. <video:content_loc> is the URL of the video file on your server and <video:player_loc> is the actual player URL.
If you can't figure out one, go for the other. To test it, just add 1 video, submit it to Google and wait until it's been crawled and see what errors (or not) it throws.