Apparently, 2013 is the year for teen sequels.  Two more #2's came out yesterday, February 5, 2013.
Unravel Me by Tahereh Mafi (Shatter Me)
Scarlet by Marissa Meyer (Cinder)
The Mafi series takes superhero fiction to a new level.  The Meyer series gives the Cinderella fairy tale a cyborg spin.  I know . . . awesome.