FX work, like acting, directing and editing, provides subjective value to a movie. What does BEST Visual FX even mean? Is there actually BEST Acting, or BEST Art Direction?
In the end, BEST is a poor choice of word for "most effective", which is what they actually mean for every single category. Back in 2005, I spent a long time dissecting this on another forum. War of the Worlds, Revenge of the Sith (not even nominated, to the howls against injustice by many SW fans), and King Kong were my discussion points.
Some readings of the award tend to think most photorealistic CG effects constitute BEST (War of the Worlds). Some think greatest number of high quality visual effects (Revenge of the Sith). I was arguiong that Kong was always going to win, because it was the most effective use of CG effects. Effects don't exist in a vacuum. Like the other disciplines, the contribute to a stew of creativity to tell a story. That voting perspective hurts films like Transformers, because the stories are so worthless. The stories are essentially the effects. The largest voting bloc is actors though. They will always vote for effects that involve the audience in the story, even they are a bit less polished.
For this reason, Rise is the film to beat in my mind. It may lose to another darling, but it marries effects with dramatic acting, and trhe effects are critical to telling THAT story (just like Kong or The Matrix). In the end, unless you truly shatter some technical barrier (like The Abyss or something), the voting will tend to favor the story over the technical aspects of the effects.
Just like every other category.