It's not anything too terribly complicated. Just different colors represent a different numerical value. It's just a graphical representation of the rep count, which if you put your mouse over the gems, it displays. I don't think too many people would start counting the rep gems to see their count. But, regardless, the old rep gems are still in the Starcraft 2 forums, and differ in style. You might like that style better. I assume when Ralle implements the Starcraft 2 resource section, that you'd be able to use the Sc2 theme.
But, Skycex, I suggest before making new threads, that you look around for stickys, or previous posts for help.
~Snap