aggravating confirm plugger

[Harry Putnam]

How can I turn off the aggravating [confirm] plugger I see whenever I
attempt to open a non-existent file.

The old thread started in November:
  Subject: C-x C-b and C-x C-f bugging about confirmation
 
 Message-ID: <address@hidden>
 
  > why on earth does C-x C-b and C-x C-f ask me to confirm when I wish to
  > open a new buffer/file?

  [Stefan wrote:]
  So as to help prevent doing it by mistake when you mistyped.
  Set confirm-nonexistent-file-or-buffer to nil to get back the old
  behavior (or just hit RET twice, of course).

But setting  confirm-nonexistent-file-or-buffer to nil hasn't turned
it off for me... maybe something has changed since then?

(I'm running todays cvs of emacs-23)