Being a turret-less vehicle, like the Stug, I hope that Bill can get them to include that that rule where the SU-122 cannot perform a Fire and Move; like the Stug and Jagepanzer is supposed to have in the Normandy expansion.
Also, I sure hope it does not get the over-run ability! The SU-122 does not have any MGs! In fact, the whole series - the SU-85, SU-100, SU-122 all based off the T-34 hull - did not have any MGs because it wasn't meant to be used to over-run infantry, instead they were purposely designed to destroy tanks.
The SU-122 was armed with a 122mmm M-1938 howitzer though, and not a 122mm AT gun. So it was used against bunkers and such, but when needed it can fire at tanks. The SU-85 and SU-100 were the Tank Destroyer with the higher velocity guns. The SU-100 being a little better, though its ROF was slower.
It needs to be noted that the SU-122 was being replaced by the more versitile SU-85 in late 1943., and the SU-100 replacing the SU-85 in early 1945. The SU-85 (and SU-100) prove to be an effective support tank when deployed in conjunction with the T-34. When SU-85's were employed as individual units, they fell pray to German anti-tank teams and guns.