After recently purchasing a MacBook Air 4.2 (2011 model) I decided it would be great to triple boot with MacOS, Windows 7 and a linux distro. After some googling I found this great article on lifehacker. This how-to follows this guide, but has been modified slightly for my installation.
Linux Mint 12 (Lisa) is based on Ubuntu 11.10 so the script created by Joshua Dillon that is referenced on the Ubuntu MacBook Air site would in theory work, however as I found I needed to do a little tweaking to get this to occur. Below are the steps that enabled me to run Mint 12 on my MacBook Air.