The device is a ZW-523 from Boca Devices. They were in the Z-wave booth, but a real quick Google search didn't find anything.
I assume it appears to the panel (JDS, etc) as if it was a TW-523, therefore the panel instantly supports the ZW-523. I don't have anything that requires a TW-523 anymore, so I didn't pay too much attention to it. Since the Z-wave protocol isn't tied to the AC zero crossing, maybe the ZW-523 operates as if it was on a 600 Hz (or something fast) powerline to gain speed? Would the panel get confused by data coming too fast? Maybe they figure that Z-wave support at slow speeds is better than no Zwave support?
Oh, and I also heard SmartHome mention a TW-523 emulator to add Insteon support for hardware panels. I told them they should also consider a CM11a or 1132U emulator so that all the HA software would instantly support Insteon also.