This is the nearest Pixar offering:
http://pixar.wikia.com/Inside_Out
I'm quite looking forward to the concept of this one, it sounds interesting and quirky.
I am curious as to how they'll create Riley though.
So far, the concept art hasn't made to the internet yet.
I'm expecting cuteness will the order of the day, be prepared for lots of "Awwww, she's so cute!" when we finally found out what she looks like.
Edit: Found a brief description, from an (unseen on the internet) animation test.
"Blonde with black headband".
I was kindof hoping she wouldn't be blonde, as it's somewhat overdone.
However, I'm expecting she won't be a typical girly girl.
Maybe there will be something offbeat about her or she'll have tomboy characteristics.
Since they're comparing her to Merida, I'm assuming she has to have a strong persona.
And since part of the film is about her dominating her environment due to personal upheaval (her family moves from a quiet town to a big city, she doesn't take it well), I expect she'll have to be quite forceful, to play off the adults (probably her parents) in the movie.
http://disney.wikia.com/wiki/Disgust looks like an interesting character, I hope they keep that design.