A few years ago I wrote an article titled Publishers' choice: Will the iPad be the hero or villain of the comic book industry? It was an open letter to comic book publishers urging them to embrace the digital distribution method to ensure comics didn't fall to the same fate as illegal music downloads. I spelled out four guidelines for a successful business model -- one that would appeal to comic book readers in the mobile computing area. Since then, the comic book industry has taken up some of the suggestions and it takes another step forward. That's because Marvel has unveiled its