I don't know if this has any bearing ...
I was just toying with the idea of buying a Mini instead of an iMac and once in the basket (Apple Store) there was a 1-2 week dispatch date for the 27" Cinema Display.
Could this lack of stock signify an imminent refresh of the 27" Cinema Display (USB 3 etc) as well as an iMac refresh? Would they be refreshed alongside of each other?
My 08 iMac's screen died a few weeks back so I need a new machine, but there is no way I'm going to buy until the refresh.
I swore I'd never buy an iMac again as I don't like the idea of it being all in one, thus something as simple as a hard drive failure requires the whole machine to be sent away for repair.
The HD failed in my iMac during the first year ... was collected by Apple Care and fixed, but it had to go back 4 times in total as the first HD replacement was dodgy, and the other times it kept coming back with dust under the screen!
However, you really do get a lot of bang for your buck with the iMac ...
So, I am HOPING that they refresh the iMac this month as I am currently having to make do with an iPad and iPhone only and they can only do so much.