Well according to an interview over at The Sci-fi Wire there's some mulling over a Dead Zone movie which hopefully would complete the series. Anthony Michael Hall isn't optimistic about it but he's open to the possibility.

Realistically it doesn't have as much of a chance as many of the other movies used to complete TV series. But I would have said the same thing about Futurama or Dead Like Me a few years back. So I'm going to be quietly optimistic about this one.

I just finished watching the end of the first season of TDZ a few moments ago, I forgot how stunning and shocking the end of the first season was. It's Genius.