The theory was based on what seemed to be a simple countdown happening with the KitKat teaser posts. On the 14th, there was a teaser involving 007, the next day saw a KitKat bugdroid in 6 pieces, after that were possible number 5s, and on Thursday was a simple KitKat bar with 4 pieces. Yesterday, we were hoping to see a reference to the number 3, which would have continued the countdown, but instead there was an image suggesting we "have a relaxing break, with a cool ocean breeze."
There are certainly no overt references to the number 3 in the image, which shows a KitKat pier reaching out into water. The image does remind us of a wider shot of the first Moto X teaser image, but there isn't much to take from that. Although it is a reach, we do like a theory suggested by a reader which is that the countdown is on a "break" and will resume Monday. If that happens, the countdown would end on October 24th, which is when Google does have an event planned. It has been said that the event will not include hardware, but that doesn't mean it won't include Android 4.4.
Whatever Google is planning should become clear this week, likely soon after the Microsoft/Nokia and Apple announcements, because that's how the game is played.