Personally, I'm happy about the elixir change.

Content is designed around what people are capable. Stacking elixir buffs as much as you can, greatly increased what people were capable of. This means encounters were tuned around that. By reducing the amount of dependancy you can place on elixirs, they can tune encounters down a bit, that previously required excessive consumables, and the accompanying farming.

It will also make some consumables cheaper, since it's an or option, not an and. People like me, who rarely use more than 1 elixirs (and even that rarely) are going to benefit from this change. People who are used to walking around with 4-5 potion buffs are going to have to adjust.

so it should result in less farming, more usable buffs, and ones that previously were less than useful (+int, +spi, +stam in groups, etc) will now be valid, useful elixirs. And, not being stacked one on top of another, they might be able to be improve other ones.

That said, i'm not sure why flasks can't be one slot, and elixirs their offensive and defensive slots, rather than the flask being both slots.

What i'm curious about is stuff like mageblood and troll's blood potions. Their hour buffs, like elixirs, and dont' have a 2 min potion cooldown. However, they're restorative in nature, not buffing. They're both "potions" by name. Mana regen in particular, is defensive, on a priest or paladin or druid....but offensive on a Mage, hunter, or warlock. And it's very much both, for a shaman. Where does it fit? in a similar vein, what about agility pots? They're definitly offensive for a rogue or hunter, but a warrior might down one for extra dodge.