I called my local store today(Photomark in Phoenix), and I asked the sales rep if she was familiar with the ZD back. Turns out the Mamiya rep was there, and had just handed her a ZD back. The Mamiya rep confirmed the free upgrade is for the 645 AF, and turns it into a 645 AFD. The Mamiya rep stated that a AFD cannot be upgraded to an AFD II.
Time frame (according to Mamiya rep as of 07-24-07) is supposedly 1 to 3 weeks away. Photomark is staying with the MSRP of $6,999 USD, plus tax, no shipping, decent support. SAMYS is saying (but not promising) $6,750 USD, plus shipping, no tax, no real support, "iffy" on delivery time, but claims 4 to 6 weeks, has no idea or information about RZ67 II D adapter plate or the AF to AFD upgrade, suggested I check the USA Mamiya web site (no thanks, what a confusing, generally useless site).
The Mamiya rep said that the adapter plate for the RB67 II D is in stock, and available right now, for about $670 USD.
One ZD back has my name on it, and I will buy it locally. Let's hope Mamiya can really deliver on time.
The Mamiya rep had no information about the 645 AFD having any problems with the new lenses, and I didn't ask about 645 AFD II upgrades, as I don't have one.
Stuart