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The Inside Social Games blog continues to track the convergence of games and social platforms, a key theme emerging in 2009 is the rapid pace of innovation happening in payments. Entrepreneurs are rapidly moving to fill the market need as social game developers increasingly turn to microtransactions to monetize their games on Facebook, MySpace, and the web through the sale of virtual goods.

This is a good read, will add it to my RSS feed for a few weeks to check it out.