So, I was told recently that the original decision for DC to relaunch all their titles with 52 new issue ones was originally planned to follow the Final Crisis series, with emphasis on the 52 worlds therein. But, at the time, though pushed for by Dan DiDio and others, it was nixed by then-publisher Paul Levitz.
Which does seem to fit in with Joe Michael Straczynski's account of a conversation with Dan DiDio about the relaunch this time – and JMS does stress later, he meant to say "relaunch" rather than "reboot".
When Dan DiDio comes out to the West Coast, we tend to get a bite for dinner to discuss projects, ideas, books and just hang. Dan is a great guy and an energetic speaker, chockful of ideas and aspirations for DC. As part of that, he shared repeatedly on and off for really more than a year his dream of rebooting the DCU and starting over.
So I felt confident that it was coming soon (which is one reason why I felt there wouldn't be a problem in the long run leaving the monthly books, since most of the things done in Superman and Wonder Woman would be erased by the reboot anyway, so ultimately it didn't matter whether I stayed or left. I just couldn't say anything at the time because I wanted to respect Dan's privacy and his desire to do what he thought was right when he thought it was right to do it.
To a degree, I think the success of Superman: Earth One was very helpful in showing that you could reboot a major character in a very personal sort of book and have it become a real hit (27 straight weeks and counting on the New York Times Bestseller List for graphic novels).
That said: end to end, top to bottom, front to back, this is Dan's dream, and he's fought long and hard to make this happen. I think it's absolutely the right move at the right moment in history. If you think about how well the Flash, Green Lantern and Atom were rebooted during the Silver Age, those books made the characters more contemporary, personal and relevant to the 70s. Imagine how much poorer the comics world would be without those reboots, if there had never been a Hal Jordan, or a Barry Allen.
Taking that approach to rebooting the majority of the DC line is a gutsy move on an unparalleled scale, and I think Dan deserves a massive round of applause for making it. The business part of the comics business has been languishing for the last several years, with decreasing sales and media attention. Something this big, this brave, is exactly the shot in the arm it needed. There's a saying in some of the British special forces: "Who dares, wins." I think this was and will be seen in future as a winning move.
Good on him for doing it.