I didn't know the vast majority of these and had only listened briefly to any of them. 2.66 BILLION views for this: https://youtu.be/9bZkp7q19f0 The other 9 are @ http://www.telegraph.co.uk/technology/0/most-watched-youtube-videos-of-all-time/
Except Gagnam, that is pure art, nothing quite like it. You may find that to be very fortunate or not, but it's still so I had seen something saying the most lucrative YT's were these ones somebody had done reviewing toys, but can't re-find it. Anyone else know what I'm talking about?