So you are saying I should get better info from somewhere else about an Imac than an Imac thread??
No, we are saying you might want to go to a forum with professional photographers. They are the ones who would care more about color accuracy than your typical MR user. They will answer your question much better then MR.
I calibrated my i7 27 inch iMac with Spyder 3. I ensured that my printer driver (R1800 Epson) is the most current and I used Photoshop 8 for processing. My camera is a Canon 40D and, so far, I have only used shots taken with my 24-70L and 100-400L lenses. My photos have matched what I see on the screen.
The largest that I have printed is 8.5x11 inches.
I have some more thoughts on your question. First, is your laptop a matte screen? Are you running Snow Leopard? Have you calibrated your screen with something better than the apple on computer calibration software? Do you have a quality Photo printer--not a run of the mill all-in-one?
Printing is the synergism of all of the above. I often think that printing is Black Magic instead of technology. I have had at least 7 different printers and have hated all of them. My new iMac is the first computer that I have used that has given me truly acceptable prints. I am blown away with the screen in comparison to Dells, Eizos, etc. It does not have a yellow cast and it does not flicker. I do not have glare because I use the computer in a place and manner that does not reflect light. I will never own a matte screen again.
If you don't get enough replies on this forum you might want to go to the dpreview mac discussion forum since it is largely frequented by photographers.
Here's the link http://forums.dpreview.com/forums/forum.asp?forum=1017
I took a quick look at some of the threads and most of the threads I saw seemed to be more computer releated Mac questions rather than strictly photography releated.
The professional labs I've used usually supply either a monitor profile, a card that can be scanned or a link to a color file. I calibrate the monitor manually with a color card. Epson recently released new drivers and icc profiles for my Epson Stylus Photo 2200 and SL. My prints at first were darker than what I wanted using CS2 until I got the settings correct. The print dialog was a little different than what was in Leopard. Now they are perfect. I also tried elements 8 and the prints were again perfect.It seems to always require seveal test prints before I get it right. This was true on windows machines as well.
So you don't notice that they seem a tad sharper, more contrasty looking on the screen when compared with the actual print?
I have been using my laptop 6 bit color and it's been hit and miss so anything has to be better.
I am thinking of adding a nec 2490 for my laptop or if I can get enough assurance I will go for the Imac.27" , one with no problems would be nice.