JPMorgan’s analyst division has upped its forecasts for the tablet market, based on strong sales of Apple’s iPad and new competition from Android, Windows and webOS devices. The company thinks 47.9 million tablets will ship this year, rising to 79.6 million in 2012. Sales of these devices will be worth $26.1 billion this year and $35.2 billion next, according to JPMorgan’s estimates. “We expect tablets to have an increasingly negative impact on PC shipments,” says the company’s Mark Moskowitz. “More than 35 percent of tablets sold in 2012 will be cannibalistic, particularly as relates to netbooks and notebooks.” With music a popular use for tablets, these predictions will be welcomed by the industry, albeit taken with a healthy pinch of salt given the nascent nature of the tablet market.