Nearly one in two iPod touch owners are unwilling to shell out between $5 and $10 to upgrade to iPhone OS 3.x because the software offers fewer features than on the iPhone. According to a Chitika Research survey, based on the sampling of traffic across its advertising network, 94.4 percent of iPhone owners run iPhone OS

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Nearly half the iPod touch users refuse to pay $5-$10 to update to iPhone OS 3.x (Geek.com)