I e-mailed the guy who runs the site and he wrote back saying that he received a crazy outline for the new Godfather movie... but didn't have sources to back it up so he ended up not posting it.

I asked him if he could elaborate on what they said and he said that he didn't have the info anymore. So it was probably someone just wanting to start a rumor for no good reason.

Even so, there are several good reasons to think that there is a new movie in the works.