The ground cannot cause a fumble only if you are ruled down in some other manner before losing control of the ball, ie. knee or elbow touching the ground.
In this case he was not ruled down prior to losing control of the fumble, so it definitely was a fumble. It is no different than him simply losing control of the ball running down the sideline, except for the hot dogging of course.
Another example of this is Adrian Peterson for OU against Texas in 2005. He leaped over a tackler not having been downed and used his off hand to try to maintain balance. Not being in good position, his ball hand also hit the ground and the ball popped loose. He had yet to be downed and lost control of the football = fumble.
I am a college football official. This tape is played as part of our training on an annual basis. While in poor taste, this move was not a fumble as the ground cannot cause a fumble and the player had control of the ball when it contacted the ground. In 2011 with the new college football rules, this indeed would draw a celebration penalty that would place the ball on the defenes 16 yard line after the ball is downed at the 1 - then adding on a 15 year celebration penalty.
LOL after watching it over a few times i actually started laughing at how much of a fail that was. He must have gotten screamed at xD
In John C. Maxwell's book "Failing Forward" he dispels the myth that failure is a bad thing. The man who has never made a mistake is taking orders from the one who made several mistakes. Sometimes what appears to be a failure at the moment is simply success trying to be born in a bigger and better way.