IMO the appeal of the Z3200 to photographers comes down to two major things:
1. The longevity of the Vivera inks.
2. The ease of maintenance (i.e. almost none required), with automatic nozzle mapping and cheap, replaceable heads, resulting in a printer that can lie dormant for months before printing with 100% reliability.
The inbuilt spectro is very nice, but not essential.
Whatever the other changes are, if these factors stay the same or are improved on, the printer will be great.
Vivera inks have a larger pigment particle size than Epson Ultrachrome K3 or HDR inks (not sure about the latest HDX inks). This probably accounts for a significant part of their better longevity. I hope that, in whatever ink formulation HP decide to use, they haven't reduced the particle size in an effort to chase gamut and, instead, improved gamut and further improved longevity by increasing the pigment load (whether through new resin/surfactant/carrier fluid formulation or through new head design).