I've got 4 of them now. They do nothing, as far as stats and skills. My personal feelings towards it are that considering its a Standard, which is a type of flag, almost like a war flag. I feel that it lets you into a certain area. Perhaps a dueling arena, or something that no one knows about or Blizz hasn't implemented yet. This also would explain the lvl90 req. Thats just my speculation though.