Just got the Nexus 7 a couple days ago. The iPad Mini would feel like an expensive downgrade for me.
Even with the large tablets, the Galaxy Note 10.1 rivals the iPad.
IMO .... It comes down to, Price and OS. Many still prefer iOS, but I'm sure those numbers are slipping. Apple can't stay on top of the tablet game with just an aluminum premium build. The difference between now and then is, Android is not looked at as just the alternative anymore.
Apple would crush the tablet game if they introduced a full OSX on an iPad. I can see them doing this in a couple years.