Who's that? He's the guy who wrote the screenplay for Zodiac, the movie that dramatized the Zodiac killer mystery from the 60's and 70's. It received excellent reviews, but not too many people turned out to see it (admittedly, myself included... guess I'll have to rent it).
In addition the studio is targeting 2009 (no doubt, summer) as the release date for the movie.
No word on whether any of the principal actors (Tobey Maguire, Kirsten Dunst, etc.) will be in the fourth film, but I'd be very happy to see Mary Jane relegated to a very minor part of the story.