Boomtown has a rather interesting user submitted article regarding the "new downloadable content" that was announced last week.

The user states that the new "Barn" downloadable map is not really a download but more an unlock code. The new map is already included in the retail game, just not accessible. He further states that after closer inspection there are 2 additional maps still hidden within the retail game, "Chateau" and "Safe".

Due to the fact that the user in question has a modded Xbox, he is able to ftp into his Xbox DVD drive & HD, and discovered the aforementioned material. Not much else at this point but if you want, check the complete user submission.