I came accross this nice little script in guild chat, and they got it from the AJ Forums I believe, so all props go to them just thought id share it here
Basically right now you cant sign for skirmish queues in groups, due to the weeks downtime in rated arena (god knows why this applys to skirmish)
/script JoinBattlefield(ArenaFrame.selection - 3, 1);
Stand next the arena guy with the match selection window open and throw that in as a command, or macro it w/e