The most popular games for Linux are evenly split. First person shooters such as Quake 3 and UT2K3 sell more copies to start with, but they trail off when the next graphics leap happens. Strategy games like Alpha Centauri still sell well for Linux, they don't sell as fast, but they last a whole lot longer. Kind of like the hare and the tortoise.

Quoted in "Linux Game Publishing - it's possible" M station (2003)