In my experience, Linux definitely has the advantage. Once I remembered to close my 5 workspaces and sorted out my graphics drivers (problems that won't affect a console-like system), Team Fortress 2 felt buttery smooth.
If I want to switch playlists while gaming on Windows, I have to hit Ctrl-Alt-Delete, click Task Manager, then click the web browser in the task bar on the bottom. Linux Mint with Cinnamon snaps me right there with an Alt-Tab.
Currently I can't play Steam on Linux because I'm stuck with with the OSS Radeon driver, which works fine for a desktop but doesn't have the performance for TF2. Whereas the ATI driver would, except it doesn't support compositing and DRI so I can't use my desktop with it.
I want gaming on Linux if only because it would light a fire under the manufacturers to fix their god damn drivers.
If I want to switch playlists while gaming on Windows, I have to hit Ctrl-Alt-Delete, click Task Manager, then click the web browser in the task bar on the bottom. Linux Mint with Cinnamon snaps me right there with an Alt-Tab.