Okay, so it’s not a movie, it’s a next gen video game. However, it is written by Dan Akroyd and Harold Ramis though. And it has all the original cast voicing their own characters (even Bill Murray). It’s set just after the end of the events of Ghostbusters 2, and is an original story, so it is effectively a sequel. Kinda like a movie tie-in game without having to go to the hassle of actually making the movie! :D
Check out the video below for more info, and game footage!