I switched from Windows to a macbook pro about 9 months ago and have mostly been happy. I'm irritated by the behavior of cut and paste regarding subfolders and files, and the different hotkeys slow me down. On the plus side, Terminal and shell scripting make the dos prompt look like a cheap toy. The hardware itself is beautifully done. There are far fewer instances where OS X annoys me, and I've yet to have a virus or spyware issue on OS X, and I haven't had to pay the antivirus "tax" of speed and money.

Overall, I prefer it to Windows, but I'm still thinking of switching to Ubuntu.