your old spell/weapon pots that give power+crit.. now just provide that major buff.. which of course (at least shouldnt) stack with ability or passive versions..
so if you have a pot chugging build, dont bother keeping Magelight or Entropy, as the buffs from the potion will not stack with the buffs from them.
this will likley see many people using their pots as before, not realizing they are no longer getting any real benefit other than the inital restore.
a example of a pre-1.6 chugging build, your Typical Sorc build, with Innerlight for crit and Crit Surge, etc, and using pots to further boost crit, would only be getting the boost of one of those abilitys..
so if you are focused on a pot chugging build, be mindful of the new buff system, you might be able to now free up a slot for an additional skill you previously had something slotted purely for a buff!
also, this change is not just limited to these Damage, crit buffs either, but even the after effect of all healing potions, which now just give a 20% boost major buff to that specific stat. because of how they work will not stack with abilities like Radiant Aura, etc.
I play every class in every situation. I love them all.