Many videos not suitable for children.
Adult supervision suggested.
I frequently watch videos on youtube and have never had a problem with malware.
I have ad and pop-up blockers, and I never click anything other than the video links.
It's a me! MasterOfTheXP from Youtube!
Youtube is great except for some problems with the player, and sometimes disables everything to do nothing to the site. That doesn't affect the security rating though.