You might find this useful as well:
#+BEGIN_SRC elisp
(defun count-words-in-subtree-or-region ()
(interactive)
(call-interactively (if (region-active-p)
'count-words-region
'count-words-in-subtree)))
#+END_SRCI bound that to M-= in org-mode to replace the default count-words, so now one command does both. :)
