Title: Only You Can Save Mankind
Author: Terry Pratchett
What it's about: Johnny Maxwell is a normal English boy who enjoys playing the occasional computer game. Fighting aliens is fun - until the aliens ask to surrender. A confused Johnny agrees to accept the surrender and to help the aliens reach safety, but upholding the bargain is harder than he thought it would be when plenty of other gamers are ready to fight aliens. Johnny has to rely on old friends and new if he wants to keep the ScreeWee safe.
What I thought: Very much a good read, with a lot of themes recognizable from the Discworld books. A good helping of What Measure Is A NonHuman? and just some general philosophizing about the nature of war, reality, and decency. The usual fare, and not too heavy-handed. Quite a lot of good humor. Quick read, though. Got through it in maybe three hours of on-and-off reading.
Overall: A good, solid book from the master.