So do you think the ball isn't in his hand in that picture, or that his knee isn't on the ground?
He’s definitely making a throwing motion as he goes down. Video also shows that the on field official had an excellent view of the play. Just as in baseball the tie goes to the runner, football replay gives the tie to the on field call. I could go either way based on the video. It’s very difficult to tell when the ball is first released and whether the force of the tackle could have caused his hand to make further contact with the ball after the release.
Here is a nifty site that lets you view the video frame by frame.
http://rowvid.com/?v=3M7Xab3E9sc