I have Command-E mapped to Safari's search bar, and Command-2 mapped to a Javascript prompt to search (which helped with a bug that seems to have disappeared in Safari 4). Since the two fields were an equal number of keystrokes away, I've never found myself entering something in the URL bar that I meant to search. (I guess if I did have to, I would Command-A-C-tab-V it to save time - not too much of a time loss.)
