I don't know what's your point with that info. That survey is far from represent the reality IMO. Even if the survey only tries to represent valve games, it falls short, really short. HL2 alone sold 4 Million copies at retail so I could bet without a doubt they have sold at least 10 millions and that there should be more than 50 million Steam users. They have 1 million samples in that survey a number that could be valid, but in this case I think it's not.
For example, the spanish Steam survey is broken. It hasn't let me send it since 2005, and there was an issue with HL2:EP2 not releasing in spanish because they saw at the survey less than 4000 spanish users, even though we are more than 100.000 making a conservative aproximation. For Valve, based on the info that I've sent, I'm still running a P4 2,5 GHz and 6800 GT. I wonder how many people are there with this same problem.
Also I highly doubt there are more 8800s than lower end 8 series cards. I doubt there are so many nv 5200, ati 9600, nv 6600 at this moment, Amd HD series are nowhere to be found...
Let's have a look at the game sales. In conjution with the number of discrete graphic cards sold we can make a better idea of the user base than with that survey:
http://en.wikipedia.org/wiki/List_of_best-selling_video_games#PC
If you look at the PC charts 50 million Sim copies have been sold. I doubt even half the gamers have bought the Sims. I know, you don't need a powerful card for the Sims, if at all, but indicates that gamers are alot more than just 10 million or 1 million as valve survey suggests.
Crysis on the other side of the performance spectrum has sold over 1 million copies. This suggest there are at least 1 million people with capable cards, but again not everybody with a new high-end card has bought Crysis, so the user base is bigger.
