Apparently so, according to Coming Soon:
After years of rumors, it appears that Ghostbuster 3 is finally moving forward and will likely do so with or without Bill Murray's involvement. Dan Aykroyd appeared on The Dennis Miller Show to discuss the project, dropping specific details about the sequel, hinting that the plan is to film in Spring of 2012 no matter what happens casting-wise.
"Yes, we will be doing the movie and hopefully with Mr. Murray," he says, "That is our hope. We have an excellent script. What we have to remember is that 'Ghostbusters' is bigger than any one component, although Billy was absolutely the lead and contributive to it in a massive way, as was the director and Harold [Ramis], myself and Sigourney [Weaver]. The concept is much larger than any individual role and the promise of 'Ghostbusters 3' is that we get to hand the equipment and the franchise down to new blood."
