From CNet:

Aspyr Media, a specialist in converting Windows games to run on Macs, announced on Monday that a version of the popular shooting game for Apple’s OS X operating system will go on sale March 19.

It’s nice to see such a big title running on almost all platforms, including game consoles (with it’s XBox version coming out on the 3rd of April).

In case you run Linux, ID Software provides a Linux version of the game also. I didn’t read the whole page but from what I could tell the distribution seems to be free, correct me if I’m wrong. In case you’re interested you can find more info here.