I can fully see why pets and mounts were taken off with how the points system is now tied into achievements.
although, the removal of 310% mounts with so many previously grandfathered into the game creates a terrible farming/gathering environment for any fresh player.
That's the only real fairness issue i've seen, it's the only one with a real tangible value to it.
But i've got to say,
http://wotlk.openwow.com/item=45047 no longer being available for me to purchase and drop next to the incapacitated lich king to ride in spring-loaded glory as he meets his demise... is heart-breaking.
You've got to know where i'm coming from with that one. Removing the fun stuff like
http://wotlk.openwow.com/item=37863 or
http://wotlk.openwow.com/item=45063 removes more from this game than the folks in charge seem to realize. =(