Fast word count function in Vim

I really like Michael Dunn's answer above but I found that when I was editing it was causing me to be unable to access the last column. So I have a minor change for the function:

function! WordCount()
   let s:old_status = v:statusmsg
   let position = getpos(".")
   exe ":silent normal g\<c-g>"
   let stat = v:statusmsg
   let s:word_count = 0
   if stat != '--No lines in buffer--'
     let s:word_count = str2nr(split(v:statusmsg)[11])
     let v:statusmsg = s:old_status
   end
   call setpos('.', position)
   return s:word_count 
endfunction

I've included it in my status line without any issues:

:set statusline=wc:%{WordCount()}

Here's a usable version of Rodrigo Queiro's idea. It doesn't change the status bar, and it restores the statusmsg variable.

function WordCount()
  let s:old_status = v:statusmsg
  exe "silent normal g\<c-g>"
  let s:word_count = str2nr(split(v:statusmsg)[11])
  let v:statusmsg = s:old_status
  return s:word_count
endfunction

This seems to be fast enough to include directly in the status line, e.g.:

:set statusline=wc:%{WordCount()}