Has Blizzard Begun Development of Diablo III?

If Blizzard is looking to hire a designer with previous RPG experience to "lead the team that designed Diablo and Diablo II", can we assume that development of Diablo III has been given the green light? It's only speculation, but it does seems logical that a third installment in the series would be next for the studio:
Blizzard North is looking for an experienced Game Designer to help lead the team that designed Diablo and Diablo II. The ideal candidate would be a talented and motivated individual with great design instincts and strong leadership skills.

Required Qualifications

  • Shipped at least one AAA title as Lead Game Designer.

  • Absolute passion for playing and making computer games.

  • Excellent verbal and written communications skills.

  • Experience with designing, tuning, and balancing games.

  • Great sense for what makes a game fun to play.

  • Ability to lead a team of designers to consensus.

Pluses

  • Experience working on RPG titles.