Well Panther at least was shown In-Game in "Old Friends" update by you in April 2008 same with Cromwell month later in "The Oasis" update.
First Normandy map was shown in July 2008 and that was Lüttich.
Well didn't find the M10 one but my point still stands, you have shown in-game screenshots before, even if no map was revealed. Actually you did it even when Eastern front was revealed, you showed 4 WIP screenshots of Bulge.