Yeah thoose are basically the same board.
I used the GA-MA78G-S2H on my last build and I love it hands down the best board I've ever personnaly used. Tons of features good overclockability rock solid stable and gigabyte support.
If you are serious about going to quad core in the near future you might want to look into one of the 790 chipset boards as they generally have more power phases. the 780 was really designed to be as energy efficient as possible so it could run hard in a cramped case with little or no fan noise for HTPC's. This will limit what phenoms are compatable with the board check the list before you buy and see if the cpu's your looking at are supported, although I'm quite sure in the future we will be seeing more energy efficient offerings in the phenom series from AMD.
Mark
IF: x="massive overclock"
THEN: PRINT "woot"