Blizzard's vice president of game design, Rob Pardo, has revealed to Eurogamer that early delays to StarCraft II's development were a result of staff being called off to work on World of Warcraft for a year.
Work on StarCraft II started in 2003, but Blizzard didn't even announce the game until 2007 - and it's not due to launch until later this year. However, despite the WOW-relayed delays, Blizzard has had a playable version of the game since late 2005.