Nice that you posted Ulichney's author page. I am a co-author of the second paper in the list, which describes a parallelizable error diffusion algorithm with amazing image quality, developed by the first author (not me), as part of her PhD thesis.

This has not been deployed in a product however, mostly because the approach mostly taken in new products is that described in the third paper in the list, which is (part of what is) marketed as "HP pixel control", which is inherently a method for color imaging, and which also opens up many new possibilities