Steam publishes your stats
Well by “your” I mean “people who opted to complete a survey and send all their data to Valve”.
Various bits of info can be seen for the month of June on their page. For instance, the most popular OS is some flavour of 10.7 (with a 65% share), whilst 3% are still languishing on 10.5.8. The most popular gaming platform is the venerable MacBook Pro (of which the 2011 models are most prevalent, followed by the mid-2009 edition), with the iMac in second place and Mac Pro users barely showing an interest. Also of note is that only a third of you game in HD resolutions or better. But I guess that will change now that you’ve all got retina-enabled MacBooks right?
There’s no juicy details on which applications Mac gamers tend to have as of yet, but that data is “coming soon”. We’ll update this post when that happens.