i think everyone gets a benefit when you use an item like a potion, but haven't seen anything to suggest picking up an item causes everyone to possess that item.
That's what I interpreted from the interview. That would make treasure hunting more fair instead of forcing people to hunt for items in single player instead, because other people are racing to pick up equipment just for themselves. Only one member getting the item would partially defeat the point of playing in groups if it only rewards the early bird.
Or you know, even if players don't automatically get the item someone picks up, at least there is another
theory, which is from what I seen where an item found remains on the map
until all players pick it up.
That would be fair too. That would encourage players to still go pick it up themselves, but at least
it will still be there for everyone to pick up (just like the ? Boxes in Lost Planet 2 and the power-ups
in Serious Sam Next Encounter co-op.) That way people don't fight over who gets the drop, but everyone still have to make their own effort to go pick up the drop themselves.
Either way works
(a. one member item obtain = instant item obtained for everyone.
Or b. item exists in castle until all pick up.)
Also I think items like potions have a limited range, a teammate might need to be nearby to receive the effects of the potion, it would encourage players to stick together when necessary and not make party healing too easy.