I think that times have changed, and Apple is more focused on getting iPhones/iPods/iPads shipped out for the holidays - not iMacs.
Not to say people don't still buy computers for the holiday season, but I think there's more of a focus on portable devices now.
To answer your question, my best guess is that there will be pre-orders for both iMacs starting up next Friday, or the Friday after (November 9th or 16th), with 21 inch orders being delivered a week later (24th or Dec. 1st).
As far as the 27 inch model, it's probably going to start shipping in VERY limited volume around December 8th. Tim Cook has already stated that there will be supply constraints.
I have a feeling if you're not in the first day or two of preorders you may not see it till January. BTO may also be a problem.
I am amazed what people tend to hear. Some people say Cook said it was limited... i dident hear that in the keynote, i even rewatched the iMac part...
I am amazed what people tend to hear. Some people say Cook said it was limited... i dident hear that in the keynote, i even rewatched the iMac part... now people claim to have heared US only but again it´s something that was not said in the keynote.
Why would it not be shipped before chrismas. Who is going to deliver the and sell the iMac on the few days between chrissmas and new years eve? And why would they not cash in on pre chrissmas sales?
This thing will be ready to be ordert soon enough to arive at chrissmas in many housholds. Everything else would be stupid.