Market research firm Gartner on Monday lowered its forecast for worldwide PC shipments for 2010, citing the iPad as the cause.

[ad#Google Adsense 300×250 in story]Gartner said it expects PC shipments to come in at about 352.4 million, a 14.3 percent increase over 2009, but down from the 17.9 percent growth of the previous forecast in September.

“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.”

Its research shows that PC shipments will reach 409 million units in 2011, a 15.9 percent gain over 2010, down from earlier estimates of 18.1 percent growth for the year.

“PCs are still seen as necessities, but the PC industry’s inability to significantly innovate and its overreliance on a business model predicated on driving volume through price declines are finally impacting the industry’s ability to induce new replacement cycles,” said George Shiffler, research director at Gartner. “As the PC market slows, vendors that differentiate themselves through services and technology innovation rather than unit volume and price will dictate the future. Even then, leading vendors will be challenged to keep PCs from losing the device ‘limelight’ to more innovative products that offer better dedicated compute capabilities.”