Saw 4: Next October.
Boasting a track record of consistency not seen since the halcyon days of the Police Academy series, the Saw flicks keep on arriving with remarkable tenacity. Whether or not this is a good thing is entirely up to you, of course -- but I don't see anyone holding a gun to the heads of the squeamish and forcing them to enjoy Jigsaw's evil schemes.
Most recent word is that Jiggy himself, Tobin Bell, has been signed "for five sequels," and also that the Sawmakers are presently scouring Southern California for a few new scribes. (Hey, you try coming up with six horrifically cinematic torture devices every dang year!) Apparently the fate of Saw 4 lies within the box office returns of next weekend's Saw 3 -- but considering that the first two films cost about $6 million combined and have grossed over $245 million around the globe, well, it doesn't take a brain scientist to figure out the math.
In related news, the Saw movies are not for children. Just sayin'.