Right now, users can upload a video to Wall, but cannot embed, say, a YouTube video. It would be good to allow this option, as well as the possibility to add a video comment in Wall.
IMHO the Wall is by far the most social-friendly element on a profile, as active "conversations" take place there, while the "Profile Comments" section should be left as pure "Guest Book" use--passive. Without the above enhancements, users will end up mixing both up.