Nate Silver had a story a couple days ago stating the election changing "October Surprise" is really a myth and the only case that you could even make the argument an "October Surprise" may have impacted the race was release of George W. Bush's drunk driving arrest records three days before the election in 2000 and even then that didn't change the end result of the race just Bush's margin of victory.
However, in this story it sounds like they are talking more about ballot box stuffing than a traditional "October Surprise."