Though it sounds like a full, separate player versus player mode is still pretty far off, the next major patch for Diablo III will introduce dueling. After patch 1.0.7 goes live soon you’ll be able to talk to an NPC named Nek the Brawler in New Tristram’s inn to access a PvP area called the Scorched Chapel.
Inside the Scorched Chapel you’ll be able to engage in one on one battles or free-for-alls with three or four players.
“The game doesn’t keep score and there are no objectives,” said Blizzard’s Wyatt Cheng in an update on the Diablo III site. “We wanted dueling to be as simple and straightforward as possible, so we created a minimalist system — we know that even without rewards and objectives, some players just want to beat each other up. Some matchups may be one-sided, and we don’t expect that battles will be necessarily balanced. But that’s okay, because dueling in Diablo III is more about kicking ass and taking names in a no-holds-barred sort of way, and this design certainly allows you to accomplish that.”
Source: FULL ARTICLE at IGN Video Games