I went to the Museum on Monday and had lunch in the very cool Cafe 2 restaurant. It's located (obviously) on the second floor of the museum and serves delicious and seasonal foods including panini, handmade pastas, salumi, artisanal cheeses, salads, and soups, and desserts.
You wait in line and then place your order and pay for it at the counter. Then they give you a flag with a number to place at your table and you wait for your food to be served. The tables are long communal tables and after a relatively short wait a waiter brings you your food. They include the tip (10%) in the price of the food so you don't have to worry about that. The food is really good. I had a Panini with prosciutto cotto, arugula, provolone cheese, and spicy mustard. It also comes with olives and pickled tomatoes. Delicious.