In other words, you can drink one potion per encounter. The debuff itself has absolutely no duration. It sticks on you until you drop combat. This is largely meaningless to the casual player, but what it will do to raiding will be rejoiced as well as reviled. Alchemists are going to take a huge hit to their income if this goes live. Yeah yeah, I know most Alchemists will say their profit is from Herbalism, but after seeing the insane prices on Haste Potions, Super Mana Potions and Flasks, I beg to differ.
I completely, 100% agree with this change, despite the loss of income to a profession. As someone who raids often, the sheer number of potions a raid burns through at the high end is just not right. Mana Potions, Ironshield Potions, more Mana Potions, Haste Potions, Destruction Potions, et cetera. This change will allow them to design bosses with the players in mind, not the potions the players are using in mind. Those consumables have always been a mandatory part of high-end raiding, and they really shouldn't be.
I think Elixirs or Flasks is pretty good, along with Potions for emergencies, not Potions for keeping myself capable of contributing. In the end, it was a goldsink, and a necessary one simply due to how the items themselves worked. They had to tune with potions in mind in the same way they had to tune encounters expecting you to be buffed with seven different Elixirs and a Flask at the dawn of The Burning Crusade. Sorry Alchemists, needing to do all of that was stupid. Flasks are still going for roughly one hundred gold a pop in BC, and I can't imagine how high they will go in Wrath. Don't worry, you'll still make profit.