I still feel burnt out on Cataclysm questing and have avoided completing zones that my various max-level alts are still missing because I just don't find it fun - even if it would benefit them by unlocking certain reputations and perks. I did manage to finally level my night elf priest to 85 the other day though, driven by the desire to see what this stretch of levelling looked like from the other side.
Mount Hyjal and Deepholm were exactly the same, but that didn't really come as a surprise since it was always obvious to me that these quests were given by neutral organisations. I still think that these two are probably my favourites of the five new zones.
I only dipped my toes into Vashj'ir briefly to unlock the portal, get my sea legs and the sea horse. From what little I saw, it reeked heavily of "superficially different but actually the same" syndrome, as I wrote about it two weeks ago. The only thing that made the experience feel different to me was the fact that I realised for the first time that Vashj'ir was actually located off the coast of Stormwind. As Horde I just got a loading screen while sailing there and assumed that the zone was placed in a separate instance, since the coast was too far away to see it anyway. In contrast, sailing there straight from Stormwind harbour and with no interruptions felt nice and immersive.
Something that has nothing to do with factions but that struck me once again was that the Vashj'ir intro quest makes no sense. First you get a summon from the Farseer/Earthspeaker who then gives you that vision of Thrall... and then they send you off to some random island off the coast to fight the other faction. Talk about a non sequitur! When I first did these quests as Horde and skimmed parts of the quest text in my drive to advance quickly, I actually thought that the boat was supposed to take me to the Maelstrom. It just makes no sense to have Thrall's call for help as an intro to a completely unrelated zone - in my opinion it should have been part of the introduction to Deepholm if anything.
I avoided Uldum and then got started on the Twilight Highlands - finally a zone with noticeable differences between Alliance and Horde! And it was quite a pleasant surprise to me too: on Horde side I didn't really like the introduction to the zone much. First Garrosh has you kicking around scared goblins and lazy orcs, and then you have to endure a twenty-minute "event" that is effectively a long, unskippable cut scene that still requires you to move on and off the blimp at the right moments (so you can't just go AFK or you'll eventually have to start all over again).
The Dragonmaw storyline is... a bit weird as well. Like I mentioned in my review of the Stonetalon story at the time, I find it kind of unpleasant when the game mirrors real life politics too closely, and a story where a large foreign power kills off the local leadership and puts rebel sympathisers in charge instead felt way too close to comfort for me, even if the lines are very clear-cut in this case, as Warchief Mor'ghor is an evil bastard and Zaela is likeable. That aside, the Horde story then sends you on missions that are all over the place and on very different ends of the seriousness spectrum, from dealing with wild dragons and evil spirits to shooting pool ponies out of goblin contraptions, which makes the whole experience feel a bit disjointed.
The Alliance version really is very, very different. Where Garrosh just continues to cement his reputation as a massive ass, Varian has you strolling around town with Anduin in tow - and that boy is freaking adorable. He actually cares about his subjects, and he wants to be a priest when he grows up, just like me! D'aww. Mercifully, the Alliance doesn't have to endure an endless travelling cut scene either; you just hop onto a plane, see it fly away and then it's fade to black and a straight cut to you already being in the Highlands.
Once there, the story flows a lot more organically as well, as you visit the various Wildhammer tribes to get them to work together and basically get to save the day by being a successful diplomat. A certain degree of humour also comes naturally to the dwarves and it doesn't feel as jarring as the contrast between the super serious business of the orcs and the utter silliness of the goblins on Horde side.
There are some parallel quests, but it's not excessive. It's also notable that there are examples of how you can use parallels to make interesting content for both sides. For example the Horde has a story where one of the Dragonmaw warlords rushes off to attack the dwarves and gets killed. You don't actually get to see this, but you see him storm off and then have to retrieve a valuable item from his corpse afterwards. On Alliance side on the other hand, you get to fight off this attack and personally get to land the killing blow on the orc. I think this is a great example of how synchronous storylines on both sides can be used to provide different experiences that add up to a more interesting whole, instead of just giving the orcs a quest to kill ten dwarves and the dwarves a quest to kill ten orcs (though those exist - and have their place - as well).
I dinged 85 not long after the Maw of Madness, and while I still intend to finish the zone, it looks like the rest is going to be a mix of neutral hubs and more "different but the same" quests, except that you get to work with Mathias Shaw instead of Garona and the Gob Squad.
All in all, I enjoyed the dwarf quests enough that I think my endeavour to level an Alliance character to cap was worth it to see those alone, but I still think that it's a bit of a shame that the developers didn't try to differentiate the experiences of the two factions more.