Brave, in my opinion, takes the best parts of Disney and the best parts of Pixar and combines them into one amazing achievement of animation. Disney and Pixar have been united since 2006, but this is the first “princess” movie that involves both Disney and Pixar (Tangled and Princess and the Frog were entirely Disney produced and distributed). I hope that the themes explored in Brave will carry through to the future Disney Princess films, for five very simple reasons.
(There are minor spoilers for the film in general, but not for the plot or ending specifically. Read at your own risk!)