Can someone please explain to me why this is only for the MBPs and the iMacs and not the MacPros? I'm sure it's simple, but I'm confused why people are thinking it would be a much later refresh date for MPs. And why wouldn't the MP's be Ivy?
MacPros have used XEON processors (server class) that have the capability of multiple processor chips (that's how they get to 12 cores, with two 6 core processors in the existing MacPro), ECC memory, capability for LOTS of memory, etc. For many PRO's, processor throughput for complex tasks, like video transcoding and rendering, as well as large photo processing, is a major consideration when out fitting their workstations.
iMacs with Ivy's may be fine, even for Pro's, but that form factor does not provide convenience expansion. I supposed there will be external Thunderbolt card cage chassis that may allow some potential for extra monitors, disk arrays, video accelerator cards, etc.
But I for one would be happy to see a "pro" form factor with Ivy Bridge even without ECC et al, but with internal expansion capability, really cranked up processor speeds (there should be better cooling in a tower or mini tower).
And since I have an old Pro now (PwerMac G5 Quad) with the 30" display, I'd just as soon not have to pay for a 27" display I don't need right now ... I don't mind a desktop (or floor standing) disk array for video storage, but I'd like lots of internal memory as well.