What does it really do?
1. Allows Worgen players to purchase a Horse (which are seen and used throughout their starting area) without becoming exalted with Stormwind.
2. Evens out the number of mounts across factions.
3. Gives players a reason to become exalted with Gilneas.
I know some players were hoping for a more unique mount, but to be honest there wasn't any other mount that really fit the Worgen. Gilneans used horses just like all other Humans, and there's no real reason why they would adopt a completely different animal.
I admit back before Cataclysm launched I was a proponent of the idea of using Worgen-curse afflicted horses that would become regular horses if a Worgen owner was in Human form while riding (everyone else would have them locked into "worgen" form), but I'll admit the ship has sailed there. Such a mount would have to be established in the Worgen starting area for it to work out.