After an immensly successful launch of Stardock's new game, Galactic Civilizations 2, someone posted on Starforce's forums about how the game was a hit without having any copy protection on it's CDs. A forum admin of Starforce replied to this with a direct link of a search on a bittorrent site for the pirated copies of the game.
Stardock was appalled that they would provide a working url to pirated copies of thier game.Right now several thousands of people are downloading the pirated version only from that web-site. Is it good for the sales? Unlikely. Good game surely would have the high sales rate even if it doesn't have any copy protection, but not because of that. Good protection is the tool, which increases the rate.