Are you sad because you wanted to become a mass-murdering space general in Civilization: Beyond Earth but your fancy Mac or Linux machine wasn't approved for faster-than-light travel? Chin up, Space Patton--today 2K announced you're go for launch.
Well, not immediately. While PC users get to play Beyond Earth starting October 24, a blog post from 2K and partner Aspyr Media only promises Mac and Linux versions for "this holiday season." Upon launch the game will be available for Mac and Linux through Steam, as well as through the Mac App Store. The Mac App Store version is oddly hamstrung, though, lacking access to both the online multiplayer mode and the free Exoplanets DLC. I'd recommend sticking to Steam on this one, which offers the aforementioned DLC and cross-platform online multiplayer.
According to the post, "Mac and Linux users are encouraged to stay informed about the progress of the Mac and Linux releases by following the Civilization: Beyond Earth Mac and Linux Dev Diary series on blog.gameagent.com."
Aspyr has a long history with Firaxis, having worked on Civilization ports for the Mac since Civilization III, so I expect these ports will run fine.
As for whether Civilization: Beyond Earth is any good? We'll have a review up later this week. For now, be sure to check out PCWorld's pre-launch coverage to learn all about alien mobs, the tech web, and the politics of Kepler 186f.