FCPX on a mac mini?

Running into too many walls with my trusty G4-Tiger 10.4 - FCP6 and thinking about upgrading.
The new MacPro is out of my budget right now so I am wondering if anyone is using a mac mini with FCPX?

If so, is there any particular processor or RAM that is necessary or which combos to avoid?

Thanks
of course I will be using the companion apps as well, so are the graphics cards in these units adequate for Motion and Compressor?