If so far no game was first argument against those who had seen a Mac only pictures, this will change in the not too distant future. Increasingly more companies start producing games out versions for Mac OS X platform and not only for Windows and consoles.
The number in this month's magazine GameInformer has long awaited game coverstory Portal 2. Some pictures and an article appears stating that the game will be played on Mac. Gates, the company producing this spring will launch a beta for Steam and in May we have an official release.
The good news continues: those who have already bought the games or have a Steam account, no need to buy new versions of Mac or new accounts.
As a former player of Half-Life and Counter Strike, can not wait to test new versions. I have played Half-Life, Counter Strike and Portal for Mac OS X application but with crossover and was an OK experience. Of course, no game has too high requirements and configuration of Mac's that I had at that time was a very potent.