Activision Blizzard COO Thomas Tippl is expecting Blizzard to release six "proven property" releases over the next three years. Tippl said at the Citi 2011 Technology Conference that this will include two expansion packs for World of Warcraft, the remaining two pieces of StarCraft 2, and Diablo III.
This would mean that Blizzard expects the third StarCraft 2 sub-game, Legacy of the Void, to hit by the end of 2014. The sixth release is a possible Diablo 3 expansion, but speculation is swirling that the Titan project could hit in that time frame too.
Tippl specifically mentioned a Diablo 3 expansion which would round out the six, but GameSpot notes that he chose his words carefully, outlining proven properties. Blizzard's secret "Titan" MMO isn't proven yet, but could still release before 2014. Rumors place it in fall of 2013.
Blizzard, meanwhile, issued a statement. "We haven't made any announcements in regard to plans beyond our current slate," a representative said. "Currently, we are focused on the next content update for Cataclysm, the upcoming release of Diablo III, and continued development on Starcraft II: Heart of the Swarm."
An unspoken issue is the supposed Diablo console plans. The company has dropped more than a few hints about such a release, but that would likely be counted as part of the six existing slated releases, rather than a separate project. It's also interesting to note that despite plans to speed up World of Warcraft expansions, Blizzard only has two slated for the next three years. This could be a sign that Blizzard will still be taking its time with expansions, or that Activision doesn't want to count on their chickens before they're hatched.