Back in 1986 Granada did a fantastic 6 part documentary on the Spanish Civil War. Each episode was an hour long and based around news reel footage from the time (much of it shot by anarchist film crews) and interviews with surviving participants. The six episodes are now up on Google video, if you've not seen them I highly recommend them.
Beevor's approach is fresh and different. He understands that much of what made the Spanish Civil War unique from a military viewpoint was the revolution that had taken place. Rather than ignoring the anarchists or treating them as a minor nuisance he puts them where they belong, at the heart of the story.
The first two weeks of the revolution were its high point. A massive wave of working class creativity was released, dealing with a thousand different problems. But these weeks were also the limit of the revolution, after taking most of Spain and controlling practically all of production the revolution stalled.
Review of an essential book for understanding the CNT and the Spanish Revolution.