From what I've seen this year:
#1. The Lego Movie
#2. Big Hero 6
#3. How to Train Your Dragon 2 (Sort of let-down by this one in comparison to the first. My expectations were super high, and I just felt like they crammed way too much plot ideas in, and most of them were really rushed and didn't have a satisifying payback aside from initial shock value. Plus, most of the humor aside from Toothless felt really out of place and shoehorned in. However, it's still super Oscar-bait-y anyways. I'll admit to listening to the soundtrack over and over again, and Toothless is adorable and worth being emotional over). 
----Oscar Nominees Stop right here, probably along with Princess Kaguya, Song of the Sea (I hope) and maybe Boxtrolls, none of which I've seen yet because they're not widely available anymore/yet----
#4. Book of Life
#5. Peabody and Mr. Sherman
#6. Rio 2 (actually, the musical numbers and animation for this movie were actually really good, and there were very pretty moments. Just...the writing and story. 

 TvTropes: The Anvillous Save-the-Rainforest Movie right here).
Overall, it's probably one of the least predictable Oscar animation categories in a long time, since most of the big studios have pretty different Oscar-worthy heavy hitters 
except Pixar. I really can't make a solid prediction. If they wanted to pick the "safest" option, then it's HTTYD2; however, The Lego Movie was even more positively recieved and successful. BH6 has Disney, so if the Academy's Disney-bias is true then that's the winner. However, for pure "artsy" merit, then it's Princess Kaguya or Song of the Sea, and Studio Ghibli is rumored to stop feature-length film production, so enough could pity vote Princess Kaguya for it to win...
 

 This will be very close.