I made the Mac conversion a few years ago, and I refuse to go back to PCs. I'll list some of the pros and cons that I have found:
The OS is simple.
As of right now there are no viruses for Macs. Be aware though that as they become more popular there will likely be some that are developed.
I've found my macs to be very durable (I've had the original MacBook Pro and the new generation titanium MacBook)
The battery life is amazing for their lap tops.
The Apple Store - You can bring in your computer and ask them questions, they can usually fix it on the spot if there are problems, and you can take classes there.
You can install windows on the Mac and have the choice of which one to use when booting up. This gets around any software that doesnt support Mac.
All those problems with Windows.... You never need to think about them again.
When Apple does upgrade the OS around every 2 years the upgrades are generally very inexpensive, and are very easilly done without any headaches.
Macs are known for their sexiness, and because of that they can charge more.
Although its gotten better, not all software is available for both Macs and PCs.
They are harder to customize.
There are some issues when using other companies' routers and such.