http://blog.camposanto.com/post/173170027579/campo-santo-news
The twelve of us at Campo Santo have agreed to join Valve, where we will maintain our jobs as video game developers and continue production on our current project, In the Valley of Gods.
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In Valve we found a group of folks who, to their core, feel the same way about the work that they do (this, you may be surprised to learn, doesn't happen every day). In us, they found a group with unique experience and valuable, diverse perspectives. It quickly became an obvious match.
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Yes, we're still making In the Valley of Gods (as a Valve game!); yes, we'll still support Firewatch; and yes, we'll still produce The Quarterly Review and our regular blog content. Thanks so much for your interest in our games and we'll see you in Washington. Cheers.