Facebook is sending the clearest message yet that it intends to implement its own virtual currency, Credits, in a way that could be mandatory. This confirms months of speculation we’ve been hearing from developers. Because Facebook takes a 30% fee on Credits purchases, the decision could negatively impact the virtual goods revenue streams of some developers now — at least in the short term. If Facebook’s plan works like it intends, spending will eventually increase and developers will benefit.

At its f8 developer conference this week, company chief executive Mark Zuckerberg told Bloomberg that “‘there’s just going to be one currency that people use’ on all apps.” Later that day, Facebook’s Deb Liu was presenting about Facebook’s Credits plans, and she was asked if Facebook would continue to allow people to use third-party virtual currency services like Social Gold. She replied: “It’s still too early to tell, Credits is still in beta.”

Together with Zuckerberg’s statement, that sounds like it could be simply “no.” Another possibility is that third party virtual currency services can continue to exist, but will just be much less used than Credits, at least partially due to incentives Facebook will give to developers who use Credits – like free marketing.

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