There's a good story about them at Wired by Michael Calore. Here's a quote from the article:
Many of us on this side of the music business (the consumer side) have been saying that the old logic is a myth, and that trading songs via P2P actually encourages people to buy more music. They are exposed to more bands and a wider variety of music. They get a chance to get excited about new music in a much more direct and natural way. They aren't told about it by an advertisement or a video. They find it on their own or a friend tells them about it. They check it out, they like it, then they go to the store and buy the CD. And they probably buy more than just that one CD while they're there.And here's another quote:
Another point proven by the Arctic Monkey's success is that the major labels are misguided about promotion and marketing. Pure word of mouth and an open trading policy actually work better than big-budget videos and full-page magazine spreads.And here's just one more:
All it took was one band from this new subculture to hit it big — really big — in order to signal that a change is needed. The major labels are still scratching their heads wondering why the kids aren't buying records they way they used to. And meanwhile, the Arctic Monkeys are selling hundreds of thousands of records and enjoying the success they made for themselves.