All in all, it really depends on what you focus on.
Goblin provides a gap opener that can be vital when repicking a flag from enemy base when efc is trying to cap or escaping a rogue.
Tauren has a short AoE stun that can be used as a extra interrupt that could impact life and death and of course AoE stunning and repicking a dropped flag. Panda has decent CC move that can be used as a interrupt or incapitating a target.
Dwarf has stoneform that works life a cleanse and does well stacked with Astral Shift while eating damage.
Draenei has as HoT that cannot be dispelled and don't need as much hit.
It really depends on what kind of player you are. Don't choose based on racials. Pick the race that YOU feel best.