Not really. Developers often don't port their games to Linux due to the small potential market, and gamers tend to stay away because of that, creating a pretty vicious cycle. However, there are some major developers that port their games to Linux. Here (Wikipedia) is a list of some commercial games that have Linux ports; many of them, such as Doom 3, Neverwinter Nights, and Unreal Tournament 3, are pretty popular games, too. That page also lists original open source games and remakes of classic games that are available on Linux (farther up the page), and lists other various Linux gaming-related items. Fedora also has a gaming version of their operating system; it includes a lot of open source games from the start, and has a download manager for getting more. I should also note that any game that isn't available on Linux can often be played using WINE.