IGN spoke to producer J.J. Abrams about the possible sequel to Cloverfield. He has spoke about it in the past, but there has been nothing concrete set.
Q: Any movement on a Cloverfield sequel?
ABRAMS: We’re talking about it, but the truth is there’s another idea that I’d rather do with the same people than do a sequel. It was a whole new thing.
Q: You mean do a different project with Drew [Goddard] and Matt [Reeves]?
ABRAMS: Drew and Matt, yeah. So my dream is to work with them again, but do something that’s… Having said that, Drew and Matt both separately have really good ideas for what it [the sequel] could be, so I don’t know, we’ll see. I know the studio wants it, but who knows…
So Paramount want to make a sequel because it made them big bucks, and only cost $30 million to make. It’s good that they have different ideas about what to do, rather than just do the obvious and have the monster come back and attack a different city with a different bunch of people with a handy camera.