I've always used double overhand when deadlifting. It is way more fun:) I've played with the over/under grip, it feels akward to me, but it is more secure.
Look real close at the picture. I'm pretty sure he is hook gripping it.
Also, he is really rounding his upper body, much like Dave Tate generally advises people. His legs are really long, I don't care if he is built to deadlift or not, look at the height he has to pull it.
Anybody have a guestimate about the weight? Over 500 lbs?