Harvard Business School's Working Knowledge has an interview with Ramon Casadesus-Masanell, a professor at Harvard Business School. Along with Andres Hervas-Drane of the Universitat Autónoma de Barcelona, Casadesus-Masanell wrote a working paper tilted "Peer-to-Peer File Sharing and the Market for Digital Information Goods" that examines the interactions between iTunes and P2P networks. The researchers call into question labels' online pricing schemes and argues that labels should take P2P traffic into considering when setting online prices. It's a good interview, here's a sample:

"Record companies have attempted to renegotiate with Apple to set higher prices for new, more popular content. Our analysis suggests that this may be a bad idea because it is precisely for popular content that p2p is a better substitute for iTunes. Rare content, on the other hand, is where p2p does not seem to work well as there are fewer peers offering it. With this initiative, record companies seem to be applying traditional "brick-and-mortar thinking" in their competition against p2p. But this is surely the wrong mindset to deal with p2p.

At the end of the day, optimal pricing is an empirical question that cannot be answered without access to proprietary data that is outside our reach. Our model, however, highlights a few factors that should be taken into consideration in the determination of optimal price. Most importantly, our research demonstrates that record companies should explicitly consider the competition from p2p networks when making pricing decisions; this is something that they do not appear to be doing presently. ...

Our analysis reveals that, contrary to intuition, prices low enough to 'kill' p2p are not optimal in large markets. The industry is better off setting higher prices and attracting those consumers ready to pay due to congestion. Coexistence with p2p, however, does result in lower prices than would otherwise be observed. We also find that legal attacks result in less sharing, harming p2p networks and helping sustain high prices"