I'm one of the lucky few with a grandfathered AT&T unlimited data plan for the iPad. I plan on keeping my iPad 3 for a little while, initially, until I see which I prefer. I know the SIM cards are not the same size, but I've been able to transfer my data plans via the AT&T website in the past from iPad 1 to iPad 2 to iPad 3 in the past. Any idea on if I'd be able to transfer the plan to my iPad mini similarly (via the AT&T website)? And... if i'd be able to transfer it back and forth between the iPad mini and iPad 3 every once in a while?