Express is the counter service. There are two locations, one in Marketplace (with a more extensive menu and more seating) and a smaller one with a more limited menu at West Side in the same building as the two table service restaurants (hereafter referred to as the Puck Complex).
Wolfgang Puck Cafe is on the first floor of the Puck Complex on the West Side. It is one TS credit on the dining plan.
Wolfgang Puck Upstairs Dining Room is on the second floor of the Puck Complex on the West Side. It is a separate restaurant from the downstairs Cafe, and does not accept the dining plan at all.
so, technically there are four separate Wolfgang Puck restaurants in Downtown Disney.