This is an interesting addition to the Ender's Game universe, one that expands on Ender's (forced) decision to leave the Solar System and become a colonial governor and what he does there. It was better than I thought it would be, actually, and I completely understand OSC's decision to hold off writing it until it could knit together Bean's story as well. Recommended.
Wow, this was different. I must have seen the movie too many times since reading the book some two decades back, because a lot of the book was strange and unfamiliar to me. The entire structure is different, for one thing; the book concentrates almost exclusively on the training of Reisman's crew and refers to the actual assault on the chateau only in passing, through the device of an after action report drafted by someone who debriefed the only member of the team to be recovered. The movie, of course, is split almost evenly between the two, and leaves out much of the Dirty Dozen's individual stories. I am amused to note that E.M. Nathanson actually looked into the records to see if such a penalty unit had actually been used by the U.S. Army in WW2, but didn't mention the use of such units by the Germans and Russians at all. Ah, well. I will say that the book is not aimed at people looking for a lot of action and things blowing up, so if that's what you expect when you come to it from the movie, you're going to be disappointed. On the other hand, if you want a story that's primarily a psychological thriller and drama, then you'll like it. I thought it was okay, but won't miss not having a copy around.