but apple is drifting towards arms that they built.
http://9to5mac.com/2012/09/15/apples-a6-isnt-an-arm-processor-design-it-is-apples-first-cpu-design/
my guess is 2013 brings us the haswell not a new arm, but it is a guess.
ARM-based Macs would require a wholesale re-write of MacOS. This will take years not months. There has been zero evidence that Apple is rewriting or even considering to rewrite MacOS for ARM.
At this point, Intel-based refresh for the 2013 Mini is as much of a guess as "sun will rise next morning" is a guess