Valve loves the Playstation 3 more than Sony does

Title Valve loves the Playstation 3 more than Sony does
Author Tom Chick
Posted in Games
When January 18, 2011

In addition to the expected PC version, Portal 2 will be out for the Xbox 360 and Playstation 3 this April..

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IMO supporting cross platform play is wasted effort. There are technical issues, plus design and balance issues. All for very little benefit. They are better off spending that time adding extra features or more levels to the game.