Personally I tend to think there can't be best roleplayer, it's like saying which book is best of all. Sure, there are things worth reading and not, but matter of fact is that it all comes down to the personal choice. Myself I too have preferences in what I like and what not, so naturally people will be choosing they like.
So, let's just enjoy the game, participate, play your characters in game, write stories, experiment with new ideas, concepts. It's a living world there each one of us making it.