War stomp does no threat or damage. It does not break any known cc...it's just a stun like any other. However I wouldn't have any other racial for trash tanking be it 5, 10 or 25 man...unless it's 5% more health. =)
I have no idea if it creates any threat. I guess a good way to test is to go out with a friend and let him pull a mob. When it runs by you stomp and see if after the stun wears off who the mobs goes after.