Blizzard Entertainment chief executive Mike Morhaime said today the company is still not committing to a 2011 release date for Diablo 3, one of its most hotly anticipated titles.

“Diablo 3 is still on track to go into external beta testing this quarter. We’re working hard to ship the game by the end of the year,” Morhaime said on the company’s quarterly earnings call. “But we can’t commit to a release date for the game yet.”

Blizzard Entertainment is letting account holders opt in to a limited beta for the game. We earlier reported that the company was just about ready to pull the trigger for a beta program.

The last Diablo game came out in 2000 and still boasts a big player base. It’s nothing compared to Blizzard Entertainment’s most popular online role-playing game, World of Warcraft, which has around 11.4 million subscribers. But the game’s hack-and-slash and loot-seeking formula proved to be popular for more than a decade. It even inspired a number of dungeon crawler copycats like Torchlight.

The Diablo games allow anywhere from two to eight players to jump into discrete games with randomly generated dungeons. The goal is to prevent the forces of Hell from taking over the world by defeating Diablo, the lord of terror, and his cohorts. Players chase after powerful items and weapons to use against other enemies and players or for trade.

The company has unveiled a new player class for Diablo 3 at its annual gaming convention Blizzcon, including the final class at last year’s convention. Diablo has taken somewhat of a backseat to Blizzard Entertainment’s larger game, World of Warcraft, and its newest release Starcraft 2: Wings of Liberty.