Invincible looks great, but on my old server you could buy a boost for like 100k so making it a low % drop chance in Cataclysm felt pointless. Mirm's Head is the most unique looking mount, but again it was sold in boosts and eveyone and their dog had it on high pop servers.
Personally, if it counts, I prefer the TCG mounts. Not everyone is willing to part with RL money for one, nor has the means to afford one in-game. As for PvE raiding it will probably be the Onyxian Drake, I've ran this raid every week on 3 characters since it was upgraded to 80 and never seen it drop. Even on high population servers you are likely to see just 1 in the capital. Ashes of Alar is pretty common now, I was logged in last night and there was FIVE outside the trade district AH O.o
I used to love Anzu before they made it easily farmable. I remember being the only BE with it on my server after I dual boxed the summon with my Druid, got a lot of comments :P
---------- Post added 2012-02-20 at 08:11 AM ----------
Should of remained a quest chain :<
Ah ah ah, that's not the blizzard way. Epics and mounts for all!
Mimirons Head > Plagued Proto (I love the colour of the inside of its mouth) > Pureblood Firehawk > Rest
I don't rate Invincible, the textures are nice but I'm a little bit "meh" when it comes to anything Arthas, he's just too... limp.
The T11 drakes look horrible, literally a dragon with pieces of broken plastic baubles that you hang on x-mas trees glued on to it, yuck.
DS drakes look kinda cool, but the similarity between normal and heroic just screams "just to tide you over until the next cash-cow is ready for milking" much like most of the second half of this expansion.
A'lar was cool when it was actually rare (and a sign of a "good" player, mainly due the way tiers worked back then) but nowadays you see dozens of (no offense Waimzer, gz on your mount bro) "bad/casual/scrubs/whatever" riding around on it and after you inspect them and realise they are not/were not ever at that level of play and just got lucky farming the place at 80/85, it kinda ruins the magic for me.
Sadly, the new chromo dragon thing is the coolest looking... But, I feel like that shouldn't count so I'm going to say the Zulian tiger.
I have it, and it's the best mount I own so I love it. I feel like it fits nicely in wow, compared to a Chinese dragon.
Immortality warponies for sure. I love the armor and the flags on the back. Invincible is the only one I use just for convenience, but the immortality ponies are just so cool because of the flags. That said, the white one looks very much better than the black one since it doesn't have the pink looking tint on the armor :/
Not sure if this is covered in your original specs OP....but the Korkron Annialator....scorpion mount...is my all time favorite...
I was dying for one since I saw it 1st right here on MMO champ...happiest day in game for me when my guild dinged 25
Still my exclusive ground mount