Ask Adobe. Anyway, it works great even if not officially supported. Just use the 'hack'. My guess is that Adobe found 9 non-Quadro cards more than enough to test extensively to give it the official 'supported' status. They know that many more non-Quadro cards work without problems, but not giving those a 'supported' status saves a lot of time and costs, not to mention support costs.
For many others, with at least 1Gig of video ram, use the nVidia Hack http://forums.adobe.com/thread/629557 - which is a simple entry in a "supported cards" file - and Mac http://www.vidmuze.com/how-to-enable-gpu-cuda-in-adobe-cs6-for-mac/