command-left arrow moves the cursor one word back; I expected command-backspace to delete a word, 
but instead OO froze.

(It appears that deleting a word should be done with alt-backspace, which is actually more mac-like. But 
that is inconsistent with using command-left arrow for moving the cursor one word. I would suggest 
using alt-left arrow for moving the cursor one word leftward, command-left arrow for moving the cursor 
completely left on a line, alt-backspace for deleting a word and command-backspace for deleting from 
the cursor to the beginning of the line. Btw: notice that alt=option)