Ford was trying to figure out if their transport van would fit in the US market and again that has stalled. They got a really great diesel and coupled with the transport, it would give sprinter a run, may even take over the market. They won't market the Mexican made Fiesta with a diesel here, even though the Eu version gets 60 mpg.
GM is a lost cause, I wouldn't but a van for any reason.
Nissan dropped the ball and it looks like they are going after the sprinter 2500 140" wheelbase market. I didn't seem much about the NV3500, it isn't in the press kit nor anywhere on line with any great amount of detail so who knows. A diesel would be great.