Just spoke with Century Optics about their accys for the HVX:

If you have a C.O. rail-type matte-box designed for the DVX100A or Z1U/FX1 (as I do) the locating pin on the mounting bracket will not fit - it's too big. The "widescreen" matte-box itself, the side wings and large french flag will work just fine, you just need the appropriate mounting plate and lens-alignment card.

The bracket designed for the HVX is in the works but no exact release date is available, although they hinted at "soon".

The 1.6x Tele-adapter will be available in a few weeks; all the wide to fisheye lenses won't be out until probably March.

Thanks. My understanding is that Century has the glass; it's the mounting hardware that still needs to be engineered and manufactured.

Centry gus came to Japan about 2 weeks ago and they are working very hard finishing those optics that I've heard from Pany guys from Osaka.
But I didn't get info about filter size: 4x4 or 4x5.65 yet.