Quote from iRacing.com forums by staff member Steve Myers:
"Some of you may be happy to know that we have been working on porting iRacing to run on Mac and Linux. By rough estimates Apple and Linux make up between 15% - 25% of the market space and as far as we can tell nothing like iRacing exists on those platforms. We are actually far enough along with this project that we have our first build to test. This is exciting for iRacing because we could see a nice jump in members with this port.
If you are a Mac or Linux user and want to get involved with testing we would appreciate the help. Please email firstname.lastname@example.org with your system specifications and what controllers you have for these systems and he will get back to you if we would like your help."
Quote from iRacing.com forums by staff member Chris Weidner:
"Thanks for the huge response to Mac / Linux testing. I've chosen the ones that I'd like to help us test and will be emailing you soon to get you started."
What is iRacing?
We are the world’s premier PC-based motorsports racing simulation. An iRacing.com membership provides entry into the newest form of competitive motorsport: internet racing. Internet racing is a fun, easy, and inexpensive way for race fans, sim racers and gamers alike to enjoy the thrill of the racetrack from the comfort of their home.
We are the ultimate place to go racing online. From NASCAR, to IndyCar, GRAND-AM, Aussie V-8 Supercars to sports cars and Grand Prix racing, iRacing has it all. All you need is a PC, a gaming wheel or game pad that simply plugs into the USB port of your computer and an Internet connection. iRacing organizes all of the racing for you with over 40 official series , or you can choose to host your own race or race in one of over 400 private leagues.