In this instance, such announcement teasers are largely redundant.  Since Oren Peli's original mico-budget Paranormal Activity made ridiculous amounts of money in October 2007, it's just been assumed that we'd be seeing new installments every Halloween until the franchise eventually becomes unprofitable.  When the Halloween without a Paranormal Activity eventually happens, we'll have stopped paying attention in favor of a new spooky holiday franchise, as was the case with the Saw movies.  Until then, though, we'll just assume that October means more found footage activities.

This admittedly brief teaser is here for your viewing pleasure courtesy of The Lebanese Cinema Movie Guide.

Catfish documentarians Henry Joost and Ariel Schulman got involved with the franchise last year, and the consensus on Paranormal Activity 3 seems to be that they proved there's still plenty of gas in the tank.  It certainly marked a commercial rebound, almost equaling the first film domestically and easily outgrossing it globally.  Joost and Schulman are back directing the fourth film, the details of which have been kept most secret.

Paranormal Activity 4 arrives in theaters from sea to shining sea on October 19th.