Playboy is about to find out how many people really do read it for the articles. The magazine that helped usher in the sexual revolution in the 1950s and '60s by bringing nudity into living rooms - or at least sock drawers - all over America announced Tuesday that it will no longer run photos of completely naked women. Starting in March, it will still feature women in provocative poses, but they will no longer be fully nude. In a way, Playboy may…