A couple of month ago, the Fraunhofer institute has shown their interactive data eyeglasses. These glasses include an OLED microdisplay on a CMOS chip that also includes an eye tracker. They now say that such devices could be ready within 2 years.
More information on the OLED device can be found here. Basically, the idea is a bi-directional OLED - which is a display and a camera in one chip. They put photo-diodes between the OLED pixels.