Being a good biased MacGirl, I get to be continuously happy because so many switch to Macs ... and seek out my help during the transition.
My standard line is that it's not the learning, it's the forgetting. Mac OS X is easy to learn, but it's not always fun to have to think about how to do things that used to be instinctive.
Switching to Mac is like driving a new car -- yeah, it's spiffy and fast, but it's frustrating when you go to turn on your blinker and hit the windshield wipers instead. But, after a week of driving, it's not a problem anymore
Harry McCracken (former editor of PC World) has a helpful column for all you new MacHeads.
Here's the link....
Windows Switcher's Guide: Getting used to a Mac