Valve has announced - in typically humourous fashion - that Portal 2 won't hit shelves (or Steam) until April 2011.

"This two month slip not only marks the shortest delay in Valve's proud tradition of delays, it represents the approaching convergence of Valve Time and Real Time," reads the press release. "Though this convergence spells doom for humanity, it will not affect the new Portal 2 release date."

The eagerly anticipated first-person puzzler is a sequel to what many claim to be the crown jewel of 2008's The Orange Box: a compilation of titles from Valve that also included Half Life 2 (and its two expansions) and Team Fortress 2. Portal was the only original property on the disc. It was also eventually released as a stand-alone downloadable title.

Portal 2 was originally scheduled for a release this Christmas before it was delayed the first time back in June (complete with humourous press announcement). The first delay came in just a week before Valve was also set to showcase Portal 2 at E3 before canceling that appearance too.

So, all going to plan, and if the release of Portal 2 doesn't spell the end of the world, you'll finally get your hands on it in April.