I think EK should do this on all their waterblocks. I don't really give a crap what it looks like, but gold is highly corrosion resistant.
It is slow to oxidise, but how much better is it than the more common alloys they use? I believe it is generally cheaper to have the nickel, copper thing they normally have but has a similar effectiveness and oxidation rate as the gold.
Edit: as it turns out they probably don't use alloys, but plating. So gold would be a nice alternative to those who desire a long living cooling block .