Continued robust consumer demand, and strong expectations for the fourth quarter, has led International Data Corporation (IDC) to increase its forecast for the worldwide media tablet market to 117.1 million units, up from its previous forecast of 107.4 million units for the year.

In the latest forecast update of the Worldwide Quarterly Tablet Tracker, the firm (www.idc.com) also revised upward its 2013 forecast number from 142.8 million units to 165.9 million units. And by 2016 worldwide shipments should reach 261.4 million units.\

“Despite ongoing economic concerns in most regions of the world, consumers continue to buy tablets in record numbers and we expect particularly strong demand in the fourth quarter,” says Tom Mainelli, research director, Mobile Connected Devices at IDC. “Apple leads the market with its iPad, and we expect its dominance to continue in the second half of the year. Still, we believe there is room in the market for others to find success, and new Android- and Windows-based products shipping in the coming months will give consumers plenty of buying options during the holiday season.”

In addition to increasing the unit totals for 2012, IDC also updated its taxonomy to include Windows-based slates in the tablet tracker. Windows tablets (which include Windows 7 tablets shipping today, and Windows RT and Windows 8 tablets shipping in the fourth quarter of 2012) are expected to grow from about 1% of the market in 2011 to 4% in 2012, on their way to 11% of the market by 2016. During those same years iOS will grow from 57.2% in 2011 to 60% in 2012, eventually slipping back to 58% by 2016; Android will slip from 38.9% to 35.3%, declining to 30.5% by 2016.

While IDC has increased its forecast for media tablets in 2012, the firm significantly lowered its forecast for eReaders in 2012. After a disappointing first half of the year, and strong indications that sub-$200 tablets are significantly impacting demand, IDC now expects 2012 shipments to top out at 23.6 million units, down from the 27.7 million units that shipped in 2011.