How long until electronic paper/pigment based monitors hit the market?

About as long as it took someone to answer this question. :)

I’ll go ahead and predict that monitors where you’ll are highly interactive won’t go to e-paper but instead to AMOLED technology for its speed and brightness and relatively low power (not less power than e-paper but less than most flat panel technologies).

But I think we will see larger e-paper displays for signboards and ads as soon as they figure out cheaper ways to fabricate the interconnects for pixel control. So I’ll further predict that in 15 years you will have some spray-on stuff with self-organizing nano-interconnects. Whole walls will be displays.