Given Apple's abandonment of Aperture and their lack of interest in the mini I suspect my next machine will be running Windows. Probably either a small form factor desktop with discrete graphics or an Ultrabook with enough oomph to be used docked as a home machine. My current mini has a good few years left in it yet, but I'm struggling to see myself buying a Macbook Pro given the price, or an iMac given that I already own a screen.
I'm running Windows 8.1.1 on my 2012 2.3 i7 mini. It runs really smooth. Given that Windows has run snappier and more responsive than OSX on every one of my Macs I can report that Windows is almost as responsive as Mavericks is on the mini. Mavericks is running on a 960GB Crucial M500 SSD. Windows boots off the crappy OEM 5400 rpm HDD.