Though Paranormal Activity cost only $11,000 to make it brought in an astounding $107 million domestically. That's bang for your buck! Paramount therefore was quick to join (and eventually win) the bidding war for Oren Peli's next flick Area 51. The $5 million budget for Area 51 is much larger than the budget for Paranormal Activity, but $5 million is still extremely low for a studio film.
Not much is known about Area 51, but what is for certain is that it will still use the "found footage" technique which worked wonders in Paranormal Activity. A release date has not been set, but a Summer 2010 release is likely. Read a bit more on Area 51 right here.