Some of you may be disapointed that the default application switching keyboard shorcut (command-tab / command-shift-tab) can't be edited somewhere. This really disturbs me because I use this shorcut A LOT in all my graphics applications, and as I'm used to changing tools with command-tab, each time I want to change a tool, I forget, and then switch to another running application :-[.
The solution is more than simple - just replace the dock. Read the rest of the article if you'd like the instructions.
[Editor's note: This is very similar to the concept of replacing the Finder with another application, which has been discussed here before. But the actual replacement of the Dock has not. I would also add that this is a very draconian solution to the command-tab switching question, and you should heed the advice to keep a backup copy of the Dock if you intend to do this. Hopefully Apple will add the ability to customize the command-tab key combo to a future OS X release.]
Instructions
you need to log as root and then make a copy of your dock and then replace it with your favorite launcher. I use Dragthing. Rename Dragthing as Dock.app and put it where the dock belongs (/System/Library/CoresServices). Check the privileges before you log out! When you log in again, the Dock will launch but it will be DragThing in my example. The result is no more 'command-tab' shorcut! :)
Some may be disapointed to lose their Customised Dock. But I use DragThing more because of multiple layers, so losing the Dock isn't too hard for me. I have what I want - erase the default shortcut.
NB1: Some may say, I just had to use KeyboardMaestro or Quickeys - they can add some switching shortcuts, BUT they don't erase/replace the apple switching default shortcut.
Now, if someone could find where the 'command-tab' is hidding in the 'real' Dock.app ! please let us know! Then I can put the original Dock back in its place. Because finally I kinda like it :)
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020116233144776