Gameplay will be set up to encourage cooperative play, supporting players in your party.
Over on the WoW Forums, Blizzard Poster Bashiok has offered further details on the cooperative play for Diablo 3 - griefing certainly won't be encouraged.
"We're - in general - not big fans of griefing for any game. It's really only "fun" for one person, and that definition of fun isn't generally something we're going to want to encourage. It's far more positive to encourage and support meaningful and skillful options and systems within a game, than a mechanic for people to instantly turn against one another for no meaningful gameplay reasons," explained Bashiok.
Bashiok continued: "We have a large focus on cooperative play for Diablo III, and the mechanics and design decisions related to multiplayer are likely going to be based on supporting and encouraging it as much as possible, and not breaking it down."
Griefing is out then, but it appears as though PvP is definitely in.
"That doesn't mean that PvP won't have its own focus, but those are details and features we aren't yet discussing," teased Bashiok.
