The report ostensibly samples "a wide swath of the online gaming market, including MMOs, console games, casual social titles, and cloud-based game offerings." It also notes a 7% decrease in online gaming subscriptions from 2008 to 2010, a period which also happens to coincide with the once-in-a-generation economic disaster that is still ongoing.
Nevertheless, Parks' Pietro Macchiarella feels that the data makes it "increasingly difficult to justify subscription fees. Thanks to social games and free-to-play MMOs, both casual and hardcore players have the option of playing quality games online for free," he says. Check out the source article at Industry Gamers.