It's more of an incomplete thought process, but criticism is welcome.
I'm not sure where this idea came from, however I'm beginning to think that Blizzard is done with major launches of expansion packs and will move to smaller building block/piecemeal patches.
Although not too dissimilar to how the game currently functions, it would see less initial content delivered and more zones opening up as the patch cycle continues. So instead of 10 zones open straight away, you have access to 3-4. And with each additional major content patch, 2-3 more zones are opened up.
Whilst overall content would be reduced it would increase the apparent amount of accessible content available to the players and would act as the carrot keeping players subscribed if they know that a major patch is just around the corner.
I'm not sure how the leveling process would work as it would limit the ability to increase the level cap beyond 5 levels without major restrictions on end game experience.
Thoughts, questions?