Not sure about how to backup/replace the proprietary flash chip in these new MacBook Airs...besides the obvious (to the former).
As for "iMac Air," seems like a silly idea. The Mac Mini is already a small form-factor desktop designed to do basic things for the everyday person with limited desk space, just as the iMac is designed to do a little more for people who don't want to buy a monitor and want better processing power and a little more graphical horsepower without shelling out half a month's income on a Mac Pro.
The i7 is a desktop CPU, for sure. I know there are i5 models for desktops, and am not sure about the i3; I'm also not certain as to which chipsets are used in the iMac...but as it's a desktop, preliminary thought process tells me it's more likely to use a desktop-grade CPU...or what would be the point of all the iMac components designed to be a step up from the Mini?
Gone are the days when budget-level desktops are basically notebook technology in a plastic case. I have a couple mid-2000 Optiplex systems at home, and both had equally interesting freakout reactions when I attempted to make them iHacks. Apple never really got on board with that...usually, you get what you pay for (including but not limited to the logo on the shiny aluminum back).
