So you look at two comics, Smallville and Green Lantern the Animated version and use those as examples that DC comics is crumbling to the ground. Bwahahahahahaha!!!
Comics in the 40's 50's and 60's sold in the millions??? Really?? In 1960 the top selling book according to publishers paid circulation was Uncle Scrooge with just over 1 million books. Superman was number 3 at 800,000. Your claim of millions is just so much hot air.
Many of DC's nu52 didnt fair very well but they at least attempted to find new audiences with titles off the beaten path instead of throwing out multiple X, Avenger, and Wolverine titles.
The comic industry is down as whole as is the entire print industry. People are finding other ways to get their information and entertainment.