Click here for a good article titled 'Clickonomics: Determining the Effect of Anti-Piracy Measures for One-Click Hosting'.
It discusses One-Click Hosters such as Megaupload and Rapidshare and how present efforts to close them are failing. It's one of the few articles to specifically consider such services, rather than piracy more broadly.
The authors, Lauinger, Syzdlowski, Onarlioglu, Wondraeck, Kirda and Kruegel (2012) ultimately conclude that reducing the demand for pirated content by providing legitimate alternatives is the best move forward, a sentiment echoed by many.
Check it out.