Personally I think the addition of 5 more nominees will hurt the category. In my mind the more films nominated, the more likely there will be films that are equally liked to cause splits in votes and allow an inferior film to triumph.
In this case say it's a fight between Up and Coraline and there are 10 votes to split. Voters 1, 2, 3, 4, and 5 all vote Up, 6, 7, 8, and 9 vote for Coraline. Little voter 10 votes Up, Up wins. Now introduce Transformers 2.
Voters 1, 2, 3 vote for Up, 4, 5, and 6 vote for Coraline. Voters 7, 8, 9, and 10 liked Up and Coraline, but couldn't choose and voted Transformers 2 because they love special effects. Up and Coraline lose because they fought each other. If either hadn't been there it's likely the other would have garnered the votes and won. By introducing more candidates you introduce more good films, which is great, but it leads to fights between the different genres that make them lose the award (2 peope like action, 2 people like drama, one drama film nominated, 2 action films = drama has a higher chance of winning). Or maybe I'm just stupid, what I'm saying certainly isn't gospel, but I'm just seeing it going like this.
Of course a nomination itself is a great honor.
. Anyways i think this could be great. Here is the trailer. 
