For the second year running, none of this year’s animated feature nominees scored nominations in any other category. That might suggest the Academy has cooled on the medium after the initial excitement of allowing Pixar’s “Up” and “Toy Story 3″ into the expanded best picture race, but no film seemed to galvanize critics and audiences in the manner of prime Pixar fare, including the studio’s own entry.By securing a nom, jolly Highland jig “Brave” has at least outdone 2011′s “Cars 2,” but the field’s B.O. champ nonetheless faces stiff competition, including parent studio Disney’s two contrasting contenders: high-tech videogame fantasy “Wreck-It Ralph,” which resembles a Pixar pic more than “Brave” does, and Tim Burton’s endearingly ramshackle stop-motion feature “Frankenweenie.” Burton’s monochrome oddity was, unsurprisingly, a box office underachiever, but voters could well spot an easy opportunity to give the singular auteur his first Oscar. The last time Burton was up for this award, for 2005′s “Corpse Bride,” he lost out to British claymation outfit Aardman Animations. This time around, Aardman pulled off the category’s biggest upset by getting its zany, widely overlooked spring release “The Pirates! Band of Misfits” (which couldn’t even nab a BAFTA nod) in ahead of “Rise of the Guardians” from DreamWorks. With another moderate commercial performer, Focus Features’ faintly Burton-esque ghost story “ParaNorman,” rounding out the category, it’s clear this branch, when presented with few crossover certainties, defaults to quirk.