Justin Bieber's "Baby" has been on youtube since Feb 2010 and is currently the most watched video recently crossing over 800mil views.

PSY who has only had the "Gangnam Style" video on youtube for 4 months is over 760,000,000 views only 40 milion views behind Bieber and climbing. Psy already flew past Jennifer Lopez "On The Floor", Eminem and Rihanna "Love The Way You Lie" and LMFAO "Party Rock Anthem" which all sat behind Bieber on most viewed on youtube

And after performing with Hammer last night at the AMAs it won't be long before Psy is king of youtube.