While speaking to BioWare's leaders slash doctors, Greg Zeschuk and Ray Muzyka, Joystiq managed to confirm that the second batch of DLC for Mass Effect (that's the first game!) would be announced and detailed soon. According to Muzyka, he was even playing it at the BioWare office slash fortress before departing for E3 2009.
Previously, it was suggested that the next Mass Effect DLC would include some sort of fight club or arena setup. So, lots of shooting in preparation for some real shooting, then.