Sigourney Weaver said in an earlier interview while she was promoting Avatar:
"I know that my little son, Oscar – who was kidnapped from me – I think he has grown up to be a Ghostbuster," also adding,
"I might be in it and I see nothing wrong with being in it, although I don't think I will have a big part in it. I think Bill Murray has a little more to do with it - he might be a ghost."
Well it looks like that big spoiler has come true because in a new interview with Bill Murray he told Mail Online:
"I'll come back in Ghostbusters III only if I get to be a ghost. I said to them, 'I'll do it if you kill me off in the first reel.' So now they are going to have me as a ghost in the film."
LEEE777 - I say go for it. A Ghostbusters movie without Murray is like Rambo with no Stallone, plus its sounds original and with a twist.