3D / OpenGL performance is a key interest for many users followed by the driver's stability, video playback performance / acceleration, and then 2D performance, and finally after that it becomes a matter of whether the Linux video driver is open-source or how it is licensed. Multi-GPU rendering (i.e. NVIDIA SLI or AMD CrossFire) was of least interest in this year's survey.
Video playback is the most common task as found by this survey followed by using visual desktop effects, gaming, data visualization, and then GPU computing (i.e. GPGPU / OpenCL).
Lastly, for reference, a vast majority of the respondents in our 2010 Linux Graphics Survey classify themselves as mainstream users.