Valve made the challenge--have 20,000 people on Steam obtain the "Stream Crosser" achievement in Left 4 Dead 2. The prize? An early release of the "Dead Air" downloadable content, a campaign taken from the original game. Well, within 24 hours of the challenge being issued, 60,774 people unlocked the achievement, and now Valve states that the "Dead Air" DLC will release earlier than its original July 22 date.
That is...if it's finished beforehand. The team is currently working out the kinks in The Terminal and Finalé segments of the campaign, and more work has to be done internally. Hopefully, we get to play "Dead Air" in L4D2 sooner rather than, say, a few hours before July 22.
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