I love it. No performance bottlenecks and I work on 36.2 megapixel RAW images and use FCPX as well.
I could add a second monitor but I'm hard pressed to find a use for one. The 27" offers plenty of real estate. If you do want a second display, keep in mind that OSX Mountain Lion doesn't support a second display in full screen, though it seems to be something Craig Federighi is going to correct in 10.9.
For Aperture, I'd be happy to have a second screen if the second one were an iPad. Use the iPad to browse through thumbnails and control the Adjust HUD with touch while the iMac shows the selected photo. Maybe Aperture 4 will come out in the next 5 years
P.S. I lied. I forgot that I hadn't upgraded the RAM yet because I can do it myself. So this whole time I've been running with 8GB RAM and have been totally fine with it. If I start to see any performance issues, I'll upgrade it to 4x that @32GB.
Very interesting! I do a lot of writing and like to have browser windows, Pages, and other info sources open at the same time, so two displays is a must. I have a 27" NEC in landscape orientation and a 24" NEC right next to it in portrait. I suppose if I go the iMac route I could keep the 24" and sell the 27".
(Side note: I do much prefer the NEC displays to Apple displays for their wider gamut and superior color fidelity. As a photographer, that matters.)
If there's no Mac Pro at WWDC, and not any hint that there will be one later, I'll have to seriously consider the iMac solution. But I'd still prefer a new Mac Pro!
