Digital BW, The Print

John: <SNIP... The HP machines utilize both the photo black, the matte black, 
and two lighter blacks so your really talking quad inks within the color set 
and they are very smooth with excellent dmax. They've got it
together.  ... >

To expand this point on the new HP Z series...
-- on the Z3100 (11+1 inks), you can print all 4 onboard neutral inks (light 
gray, gray, photo black, matte black) on matte (or fine art) media. On gloss 
or semi-gloss  media, you can recruit 3 of the four (Photo black, not Matte), 
plus the Gloss Enhancer.
-- on the Z2100 (8 inks), you get 3 neutrals on matte media, or 2 on 
gloss/semi-gloss. No Gloss Enhancer on this printer.
-- you can choose to print with ONLY the neutrals or to also tint or mix with 
color inks with advance driver controls enabled.

And no, I don't have one yet, but this is what the folks in Barcelona are 
telling me.

Harald Johnson
author, "Mastering Digital Printing, Second Edition"
digital imaging & printing consultant