We use Flickr completely to back up our photos and videos. Only issue we've run into is videos being too large, but I usually throw them into an editor and cut them apart. I'm not too worried about losing anything on Flickr and we're happy with it as our primary backup. It's also really handy for when people ask us for photos of the team, we can link them our Flickr and let them choose. Flickr also lets you apply tags and stuff which is handy.
http://flickr.com/lnstempunks