This was a very fun story. Nanotechnology has always been a fascinating topic.. the potentials are amazing. Harnessing a story around the technology is sure to be a lot of fun.
And Anderson/Beason do not disappoint. Their basic approach is that mankind is on the edge of understanding nanotech, but not there yet.. and this can lead to disastrous consequences. When they are presented with alien nanotech.. and these aliens DEFINITELY know what their doing.. our ignorance and initial fumblings create a uninterrupted tension.
I'm a sucker for conclusive endings.. and this story doesn't have one... and I applaud them for it. It fits the story. You'll
enjoy the story, don't worry.