I suspect this is a very clever part of the buzz and rumoring that adds to marketing a movie.
This came up first last week in the Hobbit Hole. Upon reflection, but still handicapped by not having seen it yet, I would hope for a Serkis nomination only if Elijah Wood and Viggo Mortenson are being pushed also, if not in supporting actor, then for Best Actor, on at least one of these works. Maybe I will feel differently when I have seen it, but I doubt it. Tough as these choices are when the work is all good, I hope Elijah and Viggo get their due for great performances in these films.