I only skimmed the paper referenced below [1]. But what I understand at the moment is, that you essentially measure the area of the screen where high quality is important (using an eye tracker). And with this you can allocate your resources better. The downside is, that the rendering looks rather strange for anyone who looks on it without proper alignment of the high quality region. So VR goggles seem to be a good candidate for the technology, if they include an eye tracker, because they guarantee a single viewer and provide a frame to attach the eye tracker.

[1] http://research.microsoft.com/apps/pubs/default.aspx?id=1766... thanks mynameismiek