Blizzard has announced that Diablo III will not have PvP when it launches, due to it not being up to standard. In a blog post, Jay Wilson wrote:
“As we’re counting down the days until we’re ready to announce a release date for Diablo III, we’ve come to realize that the PvP game and systems aren’t yet living up to our standards.
Today, we wanted to let you know that we’ve made the difficult decision to hold back the PvP Arena system and release it in a patch following the game’s launch”
The decision was made because Blizzard did not want to delay Diablo III and punish the gamers that are ” waiting to enjoy the campaign and core solo/co-op content.”
The PvP patch will launch sometime after the game’s main launch and will include mulitple Arena maps that have location themes, achievements that are focused on PvP and a match making system that will help players find opposition of a similar rank.
A release date for Diablo III is still yet to be announced and it will release on PC. There are rumours that Diablo III will also be coming to consoles.
Source: Official Blog