Here's a comparison of Quad Core vs. Dual Core. More interesting, they've got the MSI P35 NEO 2 FIR vs. the Gigabyte P35 DS3.

I bought the MSI for the heat pipe cooling solution alone. I have both Gigabyte and MSI motherboards.
Tom's Hardware tests the GO Q6600

http://www.tomshardware.com/2007/11/08/dual_vs_quad/