Apple unveiled new iMac All-in-One Computers with NVIDIA chipsets in early March. The screen sizes stayed the same at 20 and 24 inches.
Now Apple actually mentions a 17 inch iMac for $899 in an education market specific News email that is also published on the Apple site here.
It makes a lot of sense for Apple to offer a smaller "low-cost" iMac to cater to class rooms around the world and sell them in bulk.
As far as I can see the 17 inch iMac was first mentioned on Macsimum News and than went to Italy to SetteB where the link to the Apple page is mentioned. Via Gizmodo. Apple might be announcing the 17 inch iMac early next week considering they already leaked it themselves.
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