Yeah, maybe it's only the old software with new projectors. I was able to use an older version that only supported the Spyder 3 with my 4910. If they didn't change the api and the new software has the profiles to work with last years models then it should work.Actually, worst case is that only the Spyder 4 is supported. And I wouldn't bet on the new software working with the older projectors. JVC has had autocal software before last year's models and the newer (current) software definitely didn't support the older projectors.
I can only hope. I have a Spyder 4, but want my iD3 to be usable as well (as do most if not all of us).
In regards to to Spyder 4 only being supported, well that DOA and very unlikely.