After Left 4 Dead 2 shipped, hopeful souls assumed that Valve would throw all their energy into finishing Half Life 2: Episode Three. Maybe that's true but you shouldn't expect the game anytime soon.
The February 2010 issue of Game Informer
states that there won't be a new Half-Life game released in 2010. What's more, it's not even clear what form a new game would take. It could be Half-Life 2: Episode Three or it may be Half-Life 3.
GI makes no mention of Portal, the other series set in the Half-Life universe. In the summer of 2008, Valve put out a casting call for Portal 2 voice actors but we haven't heard a peep about that game since. The designer of the original game, Kim Swift, recently left Valve so we may be a long way from seeing P2 as well.
http://www.cinemablend.com/games/Rumor-No-Half-Life-In-2010-22325.html
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