5 Months Ago, Gamasutra says (in Valve: We'll Still Support Original Left 4 Dead)  CA
Newell also told Kotaku, "Doing a sequel in one year is new for Valve. But providing ongoing support for our titles after the initial launch isn't - it has been part of our philosophy since Half-Life was released ten and half years ago," said Newell, ...

And xbox360.gamespy.com says (in Valve's Gabe Newell on the Left 4 Dead 2 Boycott)  CA
Doing a sequel in one year is new for Valve. But providing ongoing support for our titles after the initial launch isn't - it has been part of our philosophy since Half-Life was released 10 and half years ago. We see no reason to change that and will ...

And Optimus.com says (in Left 4 Dead Is Not Left 4 Gotten)  PA
Doing a sequel in one year is new for Valve. But providing ongoing support for our titles after the initial launch isn't - it has been part of our philosophy since Half-Life was released ten and half years ago, We see no reason to change that and will ...