[spydez]

I use Cocoa Emacs.app. The only major keybinding change I've done so far (in 2 or 3 months of using Emacs on OS X) is Caps->Ctrl. Getting to alt/option is a thumb-contortion, so I'll probably try out Cmd->Meta soon. Only thing holding me back is the convenience of Cmd+C/X/V.

Cocoa Emacs /does/ have Mac shortcuts on by default. Not sure if they're all there, but save, cut, copy, and paste are certainly bound to the proper OS X shortcut.

As for Aquamacs, I tried it first, but had major issues trying to get it to accept my .emacs. It tries to save a ton of crap to custom-set-variables, including things I set via setq to keep my .emacs file logically laid out. It also tried to save my entire color-theme to custom-set-faces, which is an idiotic thing to do; the color-theme takes up 1111 lines in a nice elisp file off on it's own - why try to stuff it in custom-set-faces?

Anyways, just a warning - you may have issues if you try to give Aquamacs a largish .emacs file you've built up over the years on other systems. But that's probably not a problem for you since you're coming from TextMate.

I use the same .emacs at work (WinXP) as I do at home on my Mac and Linux machines, and Cocoa Emacs played well with it with minute adjustments, so I went with it.