Will Sansa Stark end up a villain or a victim?

Today, we read some hints for George R.R. Martin's The Winds of Winter and this sparked a flurry of speculation about Sansa Stark and her ultimate fate. Here are a few theories as to Sansa's future position in the Game of Thrones.

A Song of Ice and Fire spoilers below.

GoLikeHellMachine wonders if Martin is setting Sansa up to become just like the woman who tormented her:

I've been thinking they're setting up Sansa to become just like Cersei; cruel, calculating, hard. That leads me to believe I think she's going to kill Robin and marry Littlefinger instead.

Naturally, the idea of Sansa wedding Littlefinger caused some controversy, with some commenters liking the idea of Sansa and Littlefinger living nefariously ever after and others hoping that Sansa would eventually kill Littlefinger. But UnitedShoes wondered if killing the heir to the Vale would be a wise move:

I feel like killing the heir and marrying the regent wouldn't indicate much in the way of having learned to play the game, at least from the bits that have been revealed about Vale politics. It sounded like the key lords in the Vale of Arryn were loyal to Jon, tolerated Lysa because Jon liked her and she was mother to Robert, and are on the verge of revolt should anything happen to Robert, in spite of pretty openly feeling like he's not cut out to rule the Vale and being ready to stand behind Harold the Heir.

I could be wrong (it's been a while since I finished ADWD), but her and Littlerfinger's position in the Vale will have to change pretty significantly before I could expect a plan like that to not just wind up getting them both killed.

Although GoLikeHellMachine also adds that killing Sweetrobin is a move that makes sense to someone who learned the game the way Sansa did, and wonders if Joffrey's death and Cersei's current status might prompt her to reveal her true identity and try to rule the Vale.

In light of the notion that Sansa could turn out just like Cersei, LadyJillybean's speculation about Sansa is particularly interesting:

I keep thinking she's going to get pregnant at some point. Motherhood is quite an important theme and it would be interesting to see Sansa with her view on life going through that trial.

Where do you see Sansa heading in the next book? Will she keep playing the Game of Thrones, or will she fall to it?