It would be nice yo be able to post add a video to someone else model, much like renderings now. Like Cemal said more than one video would be nice as well. Other than that I can't really think of anything?
Add video the same way as rendering. (upload the file and it goes into a video folder and automatically shows up in rendering ribbon. I don't like to have to upload to YouTube first and add link. I don't really use YouTube.