What I am wondering is how the change to healing/mana totem will affect stacking. As I understand it, right how healing stream stacks but mana spring does not. After 3.1, will you still get the stacked healing? Or will it not stack at all?

Of course, if they removed the stacking on healing stream already, then this is moot.

Ooh, just realized that combining the poison and disease totems will help with those fungus giants in steamvaults!