Although plans had been for Ghostbusters III to shoot in Cleveland this year, the trade notes that the script still isn't quite ready to move forward. Ramis' planned involvement is said to have been minimal, however. The storyline will instead focus on a new generation of Ghostbusters with cameos from the original stars written into the script.
Dan Aykroyd previously said this of the plot:
"It's based on new research that's being done in particle physics by the young men and women at Columbia University… Basically, there's research being done that I can say that the world or the dimension that we live in, our four planes of existence, length, height, width and time, become threatened by some of the research that's being done. Ghostbusters — new Ghostbusters — have to come and solve the problem."
Check back for more details on the comedy franchise sequel as they become available.