When the New 52 started, we were given a five year time line where most of the characters' histories have taken place. Despite being a year into the stories, there's still a lot we don't know. We're not exactly sure what has or hasn't happened. We don't really know how certain characters first met and what events have been erased. What the zero issues are doing is filling in some of those gaps.
This week's question is should DC put out some YEAR ONE ongoing titles for different characters? Is there a need for one? There's so much we don't know like how many adventures did Barry Allen and Hal Jordan have? When did Batman first encounter Riddler? Has Superman faced Doomsday?
I suggested last December that DETECTIVE COMICS should be more like ACTION COMICS in giving us stories from the past. Which characters need to have their early days explored? What we're seeing more and more, especially with the zero issues, is the characters' histories are changing. Perhaps in the next "wave" of new titles, we could see some YEAR ONEs added.