people say i m forgetful. ( horn honking ) maybe that s why we go to so many memorable places. love the road you re on. the all-new subaru outback. tonight on nightline, the magic pill. good-bye diet, so long exercise. not exactly. but these new drugs will try to trick your brain and body into believing you re full. but do they work? and how much weight will these people lose when they try them? risky business. a porn star s hiv diagnosis sends another scare through the adult film industry. but can those who sell sex really be forced to change their ways? lisa ling investigates. plus, sweet dreams. we take an exotic journey to a birthplace of chocolate. could this be the finest tasting confection in the entire world? announcer: from the global resources of abc news, with terry moran, martin bashir and cynthia mcfadden in new york city, this is nightline, november 12th, 2009. good evening, i m terry moran. and, we re going to begin tonight with a legitimate healt