The advancement in the storyline. I love a good story; perhaps that's why I RP. But, the story in Pandaria has been beyond amazing. I feel like I'm on the edge of my seat through this whole thing. Seriously, I know there's been a lot of complaints about all of the dailies - but do them. The stories make them worth it. Anyway, I'm really excited to see what will be going down with the Isle of Thunder and Wrathion and Garrosh and all that.
MOAR PET BATTLES. POKEMANS. Blizzard has really outdone themselves with this whole pet battle thing. The generation that plays WoW the most has fond memories of the wonderful world of Pokemon, and pet battles bring us back to that without having to buy another system. Every patch has brought new challenges and new pets, and this patch is no exception. A full list of the new pets is available at WoWhead, and a lot of them look really cool. There are also rare/elite pets that you can find all over Pandaria (you can find that list here) that will have yellow paw prints over their heads instead of green, they give tasty pet XP and you work toward Beasts of Fable, which gives you a cute Red Panda!
An important aside: While on the topic of pet battles, Nim and I have been working on a really, really inclusive guide (which will be available as a PDF) that we'd like to have out before Easter. What would you all like to see in a pet battle guide? Hit me up with some feedback about that. More details will come as they are available.
Throne of Thunder. It looks like Ulduar, man. And Ulduar was amazing. Heck, Ulduar is still amazing; it's an epic experience with tons of bosses and pretty sweet looking loot. I really hope that all of the hype means that it's going to be just as cool, even in LFR. Apparently, the mechanics are staying the same between LFR and normal modes this time around, so that'll be.... interesting. We're going to need that 5% damage buff per wipe, I'm willing to bet.
Dinosaurs. Yes, please. DINOS. I've always loved dinosaurs; one of my favorite museums is the Museum of Natural History in D.C. And the fact that the Isle of Thunder is crawling with dinosaurs, and dinosaur pets, and dinosaur mounts... I am so excited. I love dinosaurs.
Taking over the farm. Finally, we get to take over the farm from Farmer Yoon, who ends up becoming on the Tiller council or something. Anyway, that means that you can use the farm as an inn (yay hearthstones) and you can start taking work orders, which will help you with the Pandaria reputations. Even though I've maxed all my reputations on Fari, I can work on the other ones to get patterns on my other toons (namely, my tailor wants her bag pattern please and thank you).
Dem satchels. This announcement made me really happy. The satchels obtained through using the coins in LFR, which only contained 28g 50s (what a freaking arbitrary number, right?) will now contain other things. Pets, mounts, consumables, anything you can imagine can be in those satchels, making them similar to the satchels you get for running as a tank or healer when there's a high demand for them for heroics.
So yes, I am really looking forward to some of the stuff that will be coming in 5.2. What are you looking forward to? Are you as excited as I am about... well, everything? If you haven't gotten a chance to look at the 5.2 patch notes from the PTR yet, here's the most recent list.