FYI, it's a non conductive dilectic grease used for sub-zero cooling. You spread it in your socket to keep condensation from building around the pins and shorting out your CPU.
I don't think thats is dielectric grease, as the area around the socket hasnt been greased, either thats some sloppy greasing, or thats thermal paste :\.
He also has it gobbed in the center of the socket which is a giveaway that it's been greased up for sub-zero cooling. And you don't grease up the mobo outside of the socket Phnom, that's what the neoprene evaporator head is for