Bioshock2 multiplayer: Why do some people's level shine?

I know this probably sounds like a "NOOB" question, and I've asked online but nobdy ever talks on Bioshock 2 multiplayer, Idk why but in the player lobby some peoples level look like there shining, they have some kind of decoration around there level, how do they get this, Do I need to register at 2k or what? any help is appreciated, thanks, Mat S.