Nexus One updated again...signs of Gingerbread?

terryjohnson16 has dropped another tidbit of information in my inbox regarding the odd updates on the Nexus One.
He has received yet another OTA update with no change log. This time it changed his firmware version from frg83 to frg83D.

Click on image for a large view.
So far he has noted no noticeable changes to his Nexus One.