Very cool video.
I've seen pictures of it, but never really got the sensation of just how big it is. It sure "looks" big.
Also, I'm sure someone here is a PAK-FA expert, so I'll ask: are the weapons for this aircraft going to be carried externally? The reason I ask is that the video in the OP's link gave some very good straight on shots and the aircraft appears to be remarkably thin.....leading me to believe the ordnance will mainly be carried externally.