How do you tell if someone's linking to their personal YouTube channel or not? I don't want to post a video link if I get banned for it...
It's generally fairly obvious when the account belongs to a member or someone else. If you post Tom Daley's coming out video, then it's probably not your account. In short, unless it actually is your account, you don't have to worry about getting banned for posting video links. People do so all the time! =]
If your really worried about content obtained from outside EC in terms of acceptability on EC: then post in the ATS asking "is this okay?" a fair number of people do that and it's really not that much of a burden(yet) on us to say "yes, that's okay" or "no, it's not okay".