I long used emacs in X11, but recently switched to Aquamacs out of sheer laziness - not wanting to recompile emacs+gtk for my new intel mac. I've tried all the various ports, and Aquamacs is my favorite 'native' port, but I actually miss the X11+gtk build I used before. There's something to be said for an emacs that feels like emacs :)

I agree that the option key is no good as Meta - Cmd is Meta in my setup.

I absolutely override the Mac keybindings. I like having M-Q as fill-paragraph, and I found that other useful commands were being hijacked by useless OS X Text Services (like M-> for end of buffer got stolen by OmniOutliner)

I have a large 1920x1200 display that I tend to use with one emacs frame maximized, and some arrangement of windows inside that frame - most often I have a full height window on the left, and two half-height windows on the right. Sometimes I use three columns of windows, and other times four equal-sized windows makes sense.

One of those windows is almost always running zsh inside ansi-term (M-x ansi-term). Some prefer shell-mode, but I think ansi-term and zsh are more useful. I don't think shell-mode and zsh cooperate too well.

Most of my work is done in python, and I just started using pymacs and ropemacs, which seem useful. Notes on them are here: http://www.enigmacurry.com/2008/05/09/emacs-as-a-powerful-py...