There are so many, it would be hard to figure that out with more than 100,000 users, and 90% of them having armatars, We'd have to take a site-wide poll.
I don't believe that. I think only 40% of the people even have armatars, as I think around 50-60% of people don't even play, with 0 points. Those are armatarless.
I think the blue fox, or of course the Cross knight. I always pick the armatar that no one else has. And they always look cool, like the warthog and the croc. =p