I really don't see what the color of a wedding dress has to do with etiquette. It's a (recent) tradition, sure, but it's not a matter for etiquette. Invitations, place settings, showers, ceremony seating, those are all matters for etiquette. Black wedding dresses are just fashion choices. Just like it's got nothing to do with etiquette if a bride wears a pink dress or a short dress or even puts on shorts and a tshirt to get married at the courthouse.
Anyway, two of the dresses they show are hardly black. They're more brown, if you ask me.
ETA: Jung Lee might be surprised in 20 years or so when brides are wearing all kinds of colors on their wedding days. There's a lot more variety now than there was when I was a kid. In another 20 years, white wedding dresses may well be seen as old fashioned and ridiculously frumpy.