Photos around the Web have already revealed the banners gracing the walls at the Moscone Convention Center in San Francisco. On them are the letters “WWDC” and the legend “One Year Later, Light-Years Ahead.” Both the letters and the words are surrounded by a blizzard of Apple App Store icons. “WWDC,” of course, means next week’s Worldwide Developers Conference, Apple’s annual mid-year show-and-tell for its third-party ecosystem partners. The icons help underscore the company’s strategy as it gets ready to fend off new big-name competitors to the iPhone.