I don't need to be able to give specifics to state that the extra copper does wick heat away from those small, but very hot hotspots better, such as around the MOSFETs especially. It probably doesn't help dissipate heat much better as simply spread it around. Still, I'd rather the motherboard be a few degrees warmer and the hottest spots several degrees cooler as that will go a fair ways towards preserving the life of the power circuitry.
Core i7 4770k 4.2Ghz
Crucial Ballistix Sport LP 1600MHz 32GB
EVGA GTX 480 HydroCopper FTW
ASUS Xonar DX
Corsair Neutron GTX 240GB | Windows 7 64-bit
Apogee XT + MCP655 & Thermochill Triple 140mm Radiator
Corsair AX1200 PSU | Cooler Master HAF-X