Ezra Klein has written a lot about various initiatives to introduce calorie info on menus - generally on menus for chains, so that every hole in the wall in the country doesn't have to send off samples to labs. There's all sorts of accusation of nanny-statism and such, but the bottom line is that, when eating out, we don't have a crucial piece of decision-making information.
So, just as an anecdata point, I was at a Steak n Shake yesterday (I was out beyond the suburbs and had to get lunch), and was trying to decide whether to get a shake (IMO the burgers are meh, but the shakes are pretty good). At first I thought I'd save some money and just get a soda*, but the sodas there are crazy expensive ($1.79!), so I figured, "Well, for an extra buck...". Then I started to think about calories (especially in winter, when I hardly get to ride my bike, I try to ease up on intake). I would have loved to know exactly what the hit was on the milkshake, since it's not like a 20 oz. soda is low-cal, but the menu didn't tell me, and so I just went with the Coke. But I wished I could have made an informed decision.
* I really don't enjoy that kind of food without a highly caloric beverage; that's just how it is