In case you missed it, Dread Central has reported movement on Phantasm 5. As can be expected, the fans are suspicious and the Phantasm camp is neither confirming nor denying anything: http://www.dreadcentral.com/news/56209/exclusive-phantasm-5-reality
I can personally vouch that something IS happening in the Phantasm world, but can't comment on the specifics just yet without a hungry silver sphere showing up at my door. Let us not forget, however, that there has been actual filming on a new Phantasm project going on since 2008 with nothing official having come out about it yet. This isn't exactly news (see here from 2009: http://phantasmarchives.blogspot.com/2009/08/secret-phantasm-project.html) and the rest of the internet seems not to have noticed this project yet.
It remains to be seen whether this new Phantasm movement involves the completion of that secret project or an entirely new venture.