This is a bit of an oddity. Instead of talking about Open Source apps running on the proprietary Microsoft Windows, this is about running Windows games on the Open Source Linux platform (with some help from the WINE project). Take a look at the Windows game compatibility testing with Linux/WINE on the blog WastingTimeWithMikeAndAri...

Linux has better Windows compatibility than Vista

The lengthy blog entry describes four test scenarios with the games Soldat (freeware), Darwina, Blackthorne, and Civilization 4. There's also a lot of comments to the article there (79 so far).