Divergent by Veronica Roth
One choice decides your friends, defines your beliefs, and determines your loyalties . . . forever.
Or, one choice can transform you.
In Veronica Roth's debut novel, Divergent, a perfect society unfolds into a dystopian world of electrifying decisions, stunning consequences, heartbreaking betrayals, and unexpected romance. (from Goodreads)
So this summary is really vague, but I've read a more detailed one somewhere and it sounds really good. Plus we just learned about divergent boundaries in my geology class, so I thought it was pretty appropriate. And it's a dystopia so you can't go wrong there. Divergent will be released on May 3, 2011.