Oh, it's not exactly orange, but more of a gold color. It's actually one of the donator ranks. There's four different-colored ones, based on the donation amount from the member. The sky blue names like mine (aka "crystal") is actually higher ranked than the gold and silver ones.
More information on donations can be found here: http://www.pokecommunity.com/showthread.php?t=25461
More information on donations can be found here: http://www.pokecommunity.com/showthread.php?t=25461