I wonder if the handful of books that are still pretty successful (Batman, Justice League, Action Comics) could have been just as successful without the reboot. Because the sales of everything else are looking pretty bad.
That's always been my arguement. I think DC's best titles have had the least changes or are touched by the hand of Johns or Morrison. The baby, though, is out with the bathwater, unless Johns restores much of the status quo with his next big crossover, which I doubt.
And look at the pull Jim Lee has, keeping his crappy Wildstorm books in print despite low sales. Impressive