Um except its not speculation? In the interview they said the mounts will be upgradeable but full details arent known yet. Soulbinds will be a tree system and there are other world benefits such as the movement speed buffs etc. Its on the Wowhead page under covenants - maybe you should go give it a read?
Im holding judgement until proper waves are sent out for Alpha/Beta testing. Any video I have seen was just Bastion but nothing is even done yet (we still dont even know covenant class moves other then mage and DK).
I understand why some people are going in guarded because we have seen this before but I feel that we dont have enough information on anything other then covenants to say if this is going to be good or bad