Linux, the gamer platform
Obviously there are many types of gamers. The one most frequently referenced as a "gamer" is the general "throw any number of ego shooters at me" type, who enjoys the same game principe over and over again with high-definition graphics and slight differences in possible interactions with the shooting parcours. Similar subtypes enjoy racing games instead or "epic roleplaying games" which have a slightly higher variety of game mechanics. All of these people share their love for very elaborate audio-visual presentation, mostly at the expense of real innovation.
Then there's the "casual gamer", whose rise is still under way with larger demographics being attracted to new gaming platforms like smartphones and pads. She/He likes very simple, addictive game mechanics that need near-to-zero introduction, therefor always being on the verge of banality.
Finally there is a third type, sometimes called the "indie gamer". What does he want? Simple: To be amazed! :-) Not (primarily) with graphics. But with innovation, with art, with massively good gameplay. Ideally a combination of all that.
Where does she/he find it? On (mostly) small games from small. independent software forges. On modern ports of those ancient 8-bit games from around the c64 era which refuse to die, because somehow they manage to transport loads more fun with their pixilated sprites than any "Call of Crysis" clone with a 3-years-value of vector graphics design and movie-esque soundtrack.
Now have a bet: Which type of gamer would dare to call Linux a real gaming platform?
Oh come on now, please have a guess! :-)
Want to know what indie games I'm talking about? Have a look at the current Humble Indie Bundle with its selection of rather dark, high quality titles. Yes, their all available for Linux. For a reason. Even better: Purchase it giving any amount of money you feel appropriate. No kidding. Just how much more independent does it get? The screenshot to the right is from the eerie dark platformer Limbo.
Have a look at Cave Story, download a copy for your operating system and experience what amounts of gameplay can be stuffed into a "dead simple" platformer with graphics from the last century (not even the very end of it). Or look for VVVVVV, whose graphics seem to be even older. I managed to die more than 1100 times to finish it. Can you top that? Or join a Teeworlds online match, another fun way to die very frequently in a simple shoot-em-up with strong emphasis on pure gameplay.
Other great and innovative games already were available in earlier "humble bundles", for example Braid a platformer where the manipulation of time is a central plot, or Osmos (see screenshot to the right) where you play a single biological cell striving to assimilate other cells to become the largest in the pool. Or Revenge of the titans, a 8-bit-nostalgic yet fresh new implementation of the tower defense model. Or And Yet It Moves, where you spin the world around your 2D self to change gravity .Or BIT.TRIP.RUNNER, reminiscent of the earliest "jump/duck in time" arcade games. Or World of Goo. Or Aquaria. Or Voxatron.
Browse through TIGSource, an excellent blog-style source about what is going on in the indie game world. It is simply incredible how much of those small game projects exist, mainly driven by people that still want to play an "obsolete" way of doing games, forgotten by the industry. Oh yes, and of course dig Minecraft! Chances are you will also grok it, like millions of other people.
P.S.: An editorial about games on Linux in german IT magazine "ct" suggested that Linux users are seldomly gamers because Linux is a game of itself. And that those small indie games would disappear once real big blockbuster titles would get available on this platform. I have to strongly disagree. Most Linux users do also have a Windows partition on their box, so they actually have a chance to play all those big games (and many of them actually do too). So the lack of choice can hardly be reason why these small and smart games exist and mostly are available for Linux.
Cave Story and Limbo screenshot from Wikipedia, used under "fair use" terms
Osmos screenshot by http://createdigitalmusic.com/ licensed under Creative Commons Attribution-Share Alike 3.0 Unported License