After installing Windows 7 in place of OS X on my MacBook Pro for work, there are only a few things I miss. But man, they were really nice. Unix shell Time Machine The first one I’ll just say if you haven’t used a Unix-like shell of some type (Bash, zsh, whatever) then it’s hard to explain. Just that you can do everything a GUI can do (save for graphics work), but much, much faster.
I’ve been working with a MacBook Pro and OS X 10.8.2, and I have to say I’m not impressed. Coming from a background that consisted almost entirely of Windows and Linux, it isn’t all it’s cracked up to be. It’s still another OS with it’s own set of problems. That said, the user interface is more consistent and usable, in a lot of cases, than Windows and especially Linux desktop environments.