You shouldn't win "KO of the year" by knocking out a shot fighter or a bum. I mean there were a TON of "omg!!!" ko's this year. Russell ko'ing that bum, wilder, some euro fight I can't think of. Point is, KO of the year not only should be an amazing KO, it should be against a top fighter or at least a contender.
Therefor, Donaire wins it, imo.