Here's yet another post I've found in which the blog author rewrote a headline after initially posting an entry without noting that the headline had been rewritten. [They aren't easy to search for.]

http://tpmelectioncentral.talkingpointsmemo.com/2007/12/edwards_camp_to_press_wake_up.php#comment-1973957

Why am I pointing these out?  Because I believe that blog authors (all authors really) do have a bias, and it's in our interest as readers to know that bias.
  If this was the New York Times, I would like the headline completely removed because the New York Times has the power to influence the public unduly by what it writes--I don't think TPM has that power, so I would like to have a fair shake at knowing an author's bias, even if it means an "unfair" headline can still be read.  I also think that using strike-through text or a note in an update is a fair way of changing a headline and keeping historical record of that change.