This slight confused article on Teleread forums seems to suggest that SiPix maybe revving-up competition for eInk in eBooks by working with a number of Taiwanese display module manufacturers (Chi Mei Optoelectronics, Chi Lin Technology, Chunghwa Picture Tubes, and Wintek).
Until now they have been pretty focused on simpler applications like updateable price-tags etc. Seeing some competition maybe not a bad thing, and they maybe try and go direct for the flexible (or at least plastic) display.
I somehow suspect this is all Polymer Vision generated in an attempt to spurr-on eInk or get them to negotiate more, not being the single source. The ceding of images (like the one above) by Polymer Vision to SiPix suggests at least a little collaboration, although I think PV are happy to see their images used anywhere and everywhere.
All told, an interesting rumor but I wouldn't put too much store in it at this stage.