Local businesses protesting the prospect of a pedestrian plaza stretching down 34th Street from the Empire State Building to Herald Square were startled to learn this week that the Bloomberg administration had dropped the plans. After seeing Herald Square itself — as well as Times Square and parts of Union Square — get handed over to commuters on two feet only, opponents thought this promenade was a done deal. Not so. Of course, this is good news for smokers, who would have suddenly been banned from lighting up on the lengthy block. What good is a lunch at Sbarro if you can’t enjoy it with a Mountain Dew and a cigarette?