The Good E-Reader site posted a review of Seiko's SBPA003, their 2nd-gen E Ink watch. The watch uses an active-matrix E Ink panel, 1.5" in size (300 PPI). Seiko says it's got a new active-matrix drivers that enable it to be very power efficient. The watch recharges via a small solar-panel (which is located around the display). The watch synchronizes automatically via signals from atomic clocks, but these aren't available in all places.
The reviewer says that the watch is great, although there's no way to sync to Android or iOS.