Researchers at Screen Digest, an industry research consultancy in London, issued a forecast for the mobile-game marketplace on Wednesday. Analysts there see the worldwide market growing by some 600 percent in the next six years. This year, revenues are expected to be a cool $1 billion--and that figure should grow to $6.4 billion in 2010. The analysts see the US market as holding more growth potential than others, but the writers of the report suggest that only by switching to a flat-rate pricing model, as is common in Asia, can North American and European carriers tap their respective markets for maximum revenues.