As of last Thursday I am a Mac OS X user - and I love it!
The latest Macs are the only platforms you can run all 3 of the major OS flavors on (my biggest reason for switching). I am running VMWare Fusion (for Windows/Unity) as well as bootcamp. My Ubuntu install is relegated to a virtual machine for now, but the hardware will run it just fine natively. Contrary to my expectations, I am really at home in OS X - the switch was quick and its complete.