So this is what Brienne of Tarth will look like in Game of Thrones season two

Gwendoline Christie-Helen as Brienne of Tarth.

I think they nailed her appearance. In the books, Brienne isn't described as a beauty queen, but she's still a badass, like most of the women in A Song of Ice and Fire series.

Picture via Twitpic. h/t The Mary Sue.

Edit: A Fantasy Reader has a bigger version of the above picture that shows her entire body.