I actually think that GB3 will be made and that 9/11 could help it out.
First, there is this article from a respectable site dated July 30, 2002
http://filmforce.ign.com/articles/366/366119p1.htmlA SCRIPT REVIEW of GB3 from this past summer. The script was the first draft written in 1999.
Second, there is a line in there that states that more than ever another ghostbusters movie would actually help in this post-9/11 world. I remember after 9/11 about how people need to feel good again, and feel good about New York again. Many people turned to the one source of Pride many New Yorkers have….Ghostbusters.
I kid you not. Ask any New Yorker and Ghostbusters is ranked up as one source of pride for the city. That and the Yankees. But seriously, many New Yorkers I've heard from have said that Ghostbusters is the one movie about New York that everyone loves. Name any other movie about New York that gives you that same fun, escapism feeling….You can't can you.
While I hope GB3 wouldn't be made to simply cash in purely on that good feeling about New York, I'm sure it would factor for the studio to make it.
I think there has been talk about GB3 and then it being shot down simply because they want to get the name out and want the attention off until it is released. I don't think they want the Star Wars syndrome where every little movie, such as when is the lunch break, spoilered on the internet for all the raging fans to see.