The core patents already have expired. They have competition, it's called Reinkstone (and their DES/cofferdam tech).
The reason e-inks are so expensive and progressing so slowly is that it's a niche product which doesn't drive much R&D spending (compared to LCDs, which sell billions per quarter and you're reading this comment on).
It's not exciting, because the patents were never a barrier to innovation in the first place. LCDs have patents up the wazoo, it doesn't stop innovation there. The core problem with e-ink - the lack of market to justify R&D spending - hasn't really changed.
The reason e-inks are so expensive and progressing so slowly is that it's a niche product which doesn't drive much R&D spending (compared to LCDs, which sell billions per quarter and you're reading this comment on).