John Cook, Valve’s director of Steam development, recently took some questions about the company’s new foray into Mac support. Among his comments is that Valve considers Steam for the Mac “to be the biggest event in Steam’s history.” Impressive for a service that, by some estimations, owns 70 percent or more of the PC game download market.

Interview: Steam on Mac OS X is ‘the biggest event in Steam’s history,’ John Cook says [Joystiq]