Born Wicked by Jessica Spotswood

Published February 7th 2012 by Putnam Juvenile
Summary from Goodreads
"Blessed with a gift..."cursed" with a secret." Everybody knows Cate Cahill and her sisters are eccentric. Too pretty, too reclusive, and far too educated for their own good. But the truth is even worse: they're witches. And if their secret is discovered by the priests of the Brotherhood, it would mean an asylum, a prison ship - or an early grave. 
Before her mother died, Cate promised to protect her sisters. But with only six months left to choose between marriage and the Sisterhood, she might not be able to keep her word . . . especially after she finds her mother's diary, uncovering a secret that could spell her family's destruction. Desperate to find alternatives to their fate, Cate starts scouring banned books and questioning rebellious new friends, all while juggling tea parties, shocking marriage proposals, and a forbidden romance with the completely unsuitable Finn Belastra. If what her mother wrote is true, the Cahill girls aren't safe. Not from the Brotherhood, the Sisterhood - not even from each other.

This book stressed me out!  I know that sounds like a bad thing, but really it just means I got sucked into the story.  I never knew who Cate could trust or what was going to happen next -- I was expecting treachery at every turn!  The world that Jessica has created is very familiar, but it has been twisted into such an interesting form.  And I loved seeing and feeling it all from Cate's point of view.   I cannot wait for the next release in this brilliant series!