Ah yes, Linux gaming. Video games have for years been split on the consoles and on Microsoft Windows. Despite the best efforts had by companies trying to find the means to port the most popular Windows games to Linux, it’s by and large been a huge failure. This is not to say that Linux gaming failed, rather that porting Windows games has been a real mixed bag.
If you are looking for Linux games from a native standpoint, there is increasingly more games being developed and many of them can be found here (games for Ubuntu). Most surprisingly is the increase in both native action games and the birth of Mangler for those who want to use Ventrilo VoIP servers instead of a VoIP solution like Mumble.
The missing piece is seeing Linux gaming break into a for profit arm of revenue for gaming developers that will help to create a new sub-industry. While many Linux users might say this is unneeded, others who play games will likely point out that multi-player games are rather limited if everyone you know is doing their gaming on another platform. It can be frustrating to say the least.