Good news: Dan Aykroyd is very confident that there will be a Ghostbusters 3 very soon. He told the Metro:
We've got a brilliant new writer on it and we'll be passing the torch on to a new generation. We're working on it to make it just right to satisfy our fans. I'm confident we'll be in production in the next year.
Bad news: Dan Aykroyd also told the Metro that Bill Murray "won't be involved." He explained:
It's sad but we're passing it on to a new generation. Ghostbusters 3 can be a successful movie without Bill. My preference would be to have him involved but at [...]