As usual, some of my friends are racing ahead through the story while I'm stuck at work earning a living. Now, I'm aware that you can't join somebody who is playing a later act, but what about joining somebody at a later point in the same act?
In Diablo II, you could skip straight from the beginning of an act to the last boss if there was somebody else in the game to portal to. Has this changed in Diablo 3, and if so, what are the new rules/mechanics involved?