Blizzard forums are down at the moment (what else is new), but apparently on the test realms there have been some changes made to mounts. They go like this:
There is now one riding skill for all factions. It has two levels: 75 and 150. 75 allows you to ride level 40 mounts, PvP mounts, dropped mounts, and AV mounts. 150 allows you to ride all racial epic mounts.
The cost structure has also changed (these are all before discounts):
Level 40 mounts now cost 10g apiece.
75 riding skill costs 90g.
Racial epic mounts now cost 100g apiece.
150 riding skill costs 900g.
If you want another faction's epic, you still have to grind exalted because they changed it awhile back that you need Exalted to even speak to the mount vendor.
All existing characters will be converted to the new system in some way. No details given, but if I were doing this, I'd give 75 riding skill to anyone who currently has a soulbound mount, and 150 riding skill to anyone who has a soulbound racial epic mount. I can also see them making the slight mistake of giving all level 40s 75 riding skill and all 60s 150 riding skill, which is a benefit to anyone who still doesn't have their mount at those levels. (My alt needs an epic...)
The other edge case that occurs to me is that faction mounts are currently bind on use... hopefully they thought of that and put some sort of requirement on them that's either faction or race (since most people don't have exalted with their own faction).
The stated reason for this is to allow people to pick up multiple faction mounts at a lower cost; I suspect that it's in preparation for flying mounts, the fast variation of which might require 225 riding skill (and some obscene amount of gold), and as a side effect to make it less helpful to buy mounts for your alts/low level guildmates by getting a [race] sergeant to buy the mount for them.
i really wonder about blizzard sometimes, this is a non-trivial change that should have been pushed out to the expansion, it just introduces a ton of potential bugs and exploits and takes away more time from the dev & testing teams that should be going towards the expansion. first it was sand and towers and now this...
Some weird things to note...
Hunters start inside Dalaran.
You start with 10K gold
100 healing pots, 80 mana pots, 80 bandages
Epic PVP gear (rank 14 weapons)
10 more epics in my bags, rings/trinkets/cloaks/zin'rokh
150 Riding Skill
999/1000 Exalted with Timbermaw Furbolgs!?
Character xfers are closed for the night, I'm going to try and transfer a 60 over tomorrow that doesn't have an epic yet, just to see what default riding skill I get.
I've also heard (but can't verify) that "prize" epic mounts only require 75 skill (AV exalted, PVP, ZG, Baron)