I doubt branching would stop them from releasing new content for Classic WOW, if only people would be interested in playing that and paying for the game. I am

I doubt branching would stop them from releasing new content for Classic WOW, if only people would be interested in playing that and paying for the game. I am sure they won't do full blown expansion for Classic, but new content within lvl 60 cap does actually make sense. It's also possible, that at some point, when people get bored with this content they can bump the tier to TBC (1st expansion). They could probably also keep all of those running at the same time, and people could choose which tier they wan't to stop them. It all comes down to people voting with their wallets I guess.