Rising demand for tablet devices such as Apple’s iPad will weaken the traditional PC market this year and next, according to research firms Gartner and IDC. Yesterday Gartner revised its PC sales forecast, stating that worldwide PC shipments in 2010 will total 352.4 million; this is a 14.3 percent increase from 2009 (but down from Gartner’s previous forecast in September of 17.9 percent growth). Meanwhile 2011 worldwide PC shipments are forecast to reach 409 million units, a 15.9 percent increase from 2010. This is down from Gartner’s earlier estimate of 18.1 percent growth for 2011. “These results reflect marked reductions in expected near-term unit growth based on expectations of weaker consumer demand, due in no small part to growing user interest in media tablets such as the iPad,” said Ranjit Atwal, research director at Gartner. “Over the longer term, media tablets are expected to displace around 10 percent of PC units by 2014.” Gartner research analyst Raphael Vasquez added that “next-generation smartphones” will also weaken the PC market in future: “These devices will be increasingly embraced as complements if not substitutes for PCs where voice and light data consumption are desired.”

A Reuters report noted that market researcher IDC also said it was seeing a similar trend, though a spokesman said sales were still poised to grow in the double digits. IDC will update its forecast in mid-December. In October Gartner forecast that worldwide media tablet sales to end users will reach 19.5 million units in 2010, mainly thanks to Apple’s iconic tablet device. Gartner believes media tablets are poised for strong growth with worldwide end user sales projected to total 54.8 million units in 2011, up 181 percent from 2010, and will surpass 208 million units in 2014.