Aspyr's Glenda Adams and Brad Oliver are in the porting business. Fortunately they also publish and port games for other platforms. According to Brad "if Mac sales tank, we've got enough revenue coming in from PC and console ports that it probably won't hurt the company too much and we'd just focus on the other platforms." Mac game sales will only tank if people stop buying Mac games and instead play their games in Windows but as Andrew says, "people will get sick of dual-booting, and would prefer to run native games, just like Linux users prefer native games".
Ian Lynch Smith of Freeverse points out that this may be only the first step: "Apple is pushing the intel roll out very aggressively, and now aggressively pushing dual boot (and virtualization eventually from someone)". Hopefully in the next 6 months we'll see effective virtualization of Windows games from within OS X. That's the most desirable outcome for both Mac users and developers.