With the long-awaited Diablo III due out in May some 12 years after the release of Diablo II, we decided to take a look back at the release history of the company that puts out a new game "When it's done."
Aside for the Warcraft franchise, which has seen pretty regular releases since 2002, Blizzard's release schedule is a study in empty spaces. Even World of Warcraft's expansions are pretty staggered, especially considering the original plan was to release a new expansion pack every year after Burning Crusade.
Considering the company's track record of hits and misses, I'd say this timeline could serve as a blueprint for other developers; a prime example of how you don't need a new game every year to be a success.
Note that we also included games from before Blizzard was Blizzard, though we omitted Silicon & Synapse's ports, as they don't count.