GOG.com is having its fall conference right now. They've just announced that they're going be selling 50 Mac games to start with - 28 of them only on GOG - including both indie and classic titles. (e.g. Syndicate, FTL, The Witcher 1, etc ...) Like Steam it seems you'll get both versions for one price. Many of the classic games look like DOSBox games plus at least one WINE port - the newer/indie games are native. The Witcher 2 will be sold on GOG.com is a native Mac version.
As always they will be DRM-free.
As always they will be DRM-free.