Trainworld had Mike Wolf from MTH trains interview on their facebook page this morning live from the York show. He stated that the dash 8 6 wheel trucks were delayed for some type of motor life testing issue that it now passed. G scale is at about the 14 min mark.
It was interesting that just before the 11 min mark, he stated that the newest SD70ACE painted for UP honoring veterans, would be highly desired by the G scale crowd. I'm not sure if that was just to tease us?
He also talked about the new gauge one GS4 having modifications to the frame, front truck, etc. as well as the new features. I think he said it's around 3 months out still.