>Could this simply be the fact I am holding them not under >direct light and the fact the iMac is backlit? (I used to use >a 2003 Mac Powerbook and the screen was as more of a flattened >angle. I can see now why laptops are so notoriously hard to >calibrate.)
Yes, and then some.
I believe the sad truth is that the best lighting for viewing prints is poor for viewing a monitor, and vice versa.
In the book 'Real World Color Managment', they recommend that you never hold a print up along side a monitor to compare. You should have a viewing booth with proper lighting that is off to the side so you have to turn your head and cannot look at both at once. You should also shield the monitor so that the light from the viewing area does not shine on it.
The fact that the monitor is an emmitve device whereas the print is a reflective medium makes a hugh difference.
As to calibrating laptops screens, I believe the main problem with them is that many of the screens are only TN panels which have a limited vieiwing angle, and many of them are only 6-bit devices that use dithering to simulate an 8-bit color depth.