Are you trying to base the sound of their music by the looks on their faces.
Some of the most amazing sets I have heard have a similar look. Skipper is right - we can't see the crowd.
But take a look at the Mills thread, if you don't see the crowd and the lights and just look at his face - he looks pretty bored too. I remember when Richie never changed his expression during his entire set. I remember losing my mind and wondering how they could seem so away from it all.
I hope I am wrong, but making a gurning face does'nt make it sound better does it?