John Scalzi - The Ghost Brigades

The sequel to Old Man's War and I thought this one was even better than the first.  Compiling storyline, some mystery, and an evil genius, what more could you want from a Sci-Fi story.  Either way the Ghost Brigades is a great storyline and Sagan is a strong female character that is easy to like.  All in all a great book and a decent gotcha for an ending.  Also if the author had the time wrting a series following ghost troopers would be awesome!