Abel00: All the chips are tested at the wafer level( POET's claim to fame, remember guys?)

Yeah, that's an advantage of VCSEL (Vertical Cavity Surface Emitting Laser) above EEL (Edge Emitting Laser). While the former emits light perpendicular to the wafer's surface, the latter emits light at its edge, i.e. in parallel to the wafer's surface. Thus the wafer has to be sawed into chips to test each of them individually.