I was wondering if there's a way to enable multi finger gesture support in Kubuntu 12.10. I specifically would like to quickly be able to change desktop or minimise apps. Other functionality would be great too - I guess I like the OSX way of doing it.
Sorry, there is not multi finger gesture support in Kubuntu 12.10. At least in the way you describe.
But just in case some people comes here looking for help configuring their desktop environment, there are several options to change from desktops or minimize apps using the keyboard.
In the system preferences app "K-> Applications -> system preferences": Go to Shortcuts and Gestures. On the left go to Global Keyboard Shortcuts. On the Top menu called "KDE component" select KWin. you could now edit all shortcuts of the desktop environment.
NICE TIP: you can save and load configuration files with all your favorites shortcuts for each component of KDE.
In newer KDE versions there is a new tool called Mouse Gestures that provides some functionality similar to the one described in your question.
There are more information related in: System Settings/Shortcuts and Gestures