Most Zynga games are free. The company makes money from a small core of dedicated users who buy virtual goods like tractors in FarmVille. Over the last year, the average daily amount of money Zynga took in from these core users dropped 10 percent even as the overall number of users expanded.

“Zynga’s challenge has been to drive up efforts to keep their attention and broaden their user base — which they did — but now they need to get them to pay,” said Michael Gartenberg of Gartner. “Increasing the number of players doesn’t mean you’re making money off them.”

Mr. Gartenberg added a thought that would bring chills to any Zynga executive: “At the end of the day, though, virtual goods might not be a viable business strategy. People eventually stop spending money in virtual goods and want to spend that money on real goods.”

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Free-to-play, yes that is an interesting question.

DisappointmentVille.

Games is a very fickle business. It can turn on you very, very quickly.