This whole Mini sim thing annoys the crap out of me, just like the Micro-USB standard. Why the hell to the Europeans keep insisting on changing De-facto standards so that they can define new "Standards?"
Anyway, I'm annoyed they did this. I saw an article however on some tech blog (I think engadget) saying that TMobile USA has already confirmed that they will be bringing this new Sim form factor to the US to support some GPS gizmo of theirs. Plus, if they are smart, they'll offer it as an option for iPad users.
It still annoys the hell out of me though because the #1 reason I like GSM technology is when I travel I can buy local sims. Well now its just a much bigger PITA.