Well, had a great day with it. My 2006 Mac Pro 2.66 Quad runs OS X Server so it was always busy with other stuff, but the 27" i7 iMac smashes it to bits in terms of perceived performance - installing stuff, opening apps, hell you'd think there was a solid state drive in there.
I opted for the 2TB drive. My office has a few computers in but isn't noisy. I haven't heard any sounds out of my iMac at all other than the speakers.
But the screen. Wow. Next to my colleagues 30" ACD (I had to steal it when mine broke) it looks much more vibrant, crisper, and whiter. The backlighting is even and there are no dead or stuck pixels.
Fantastic value for what you actually get. I'm very happy with my choice. The Mac Pro is now headless and can continue doing what it was actually intended for.
I hope you all enjoy your machines, too, when they arrive.
Ordered 4th Jan. Delivered 27th Jan. UK Business store (ordered via sales rep on the phone, tracked online).