As the commercials say "it just works". That's true. Things seem to work more simplky, so far in my experience. Fewer clicks to get things done. Fewer software and driver issues.

Mac OS X is much more stable than Windows. It's also much less resource intensive, and runs faster (and consequently apps run faster) on equivalent machines compared to Windows.

One small thing I really like so far is the sleep mode on Macs. My iBook goes from asleep to fully functional in literally 2-3 seconds, and it boots from shutdown in about 15 seconds. My windows PC's all take much longer to wake up, not to mention they take forever to boot.

With the new MacBooks, you wouldn't even have to give up any M$ dependent apps you currently use, as you can also install Windows using Boot Camp or Parallels.

Plus there's the smug satisfaction of not supporting Micro$haft.