Market analyst firm Gartner today lowered its Personal Computer (PC) shipment forecast for 2011 and 2012, based on expectations of weaker demand for mobile consumer PCs.

Worldwide PC shipments are forecast to reach 387.8 million units in 2011, a 10.5 per cent increase from 2010, according to Gartner's preliminary forecast. This is down by 15.9 per cent from the previous projection made by Gartner early this year.

Gartner expects worldwide PC shipments to total 440.6 million units in 2012, a 13.6 per cent increase from 2011.

This is down from Gartner's previous outlook of 14.8 per cent growth for 2012.

"These results reflect marked reductions in expected near-term unit growth based on expectations of weaker consumer mobile PC demand, in no small part because of the near-term weakness expected in China's mobile PC market, but also because of a general loss in consumer enthusiasm for mobile PCs," Gartner research director Ranjit Atwal said in a statement.

Gartner analysts said that consumer mobile PCs have been the dynamic growth engine of the PC market over the past five years, averaging annual growth rates approaching 40 per cent.

For much of this period, mobile PCs remained consumers' platform of choice for bringing the Internet into their daily lives.

However, due to the spread of low-cost embedded Wi-Fi modules, an user is now able to access the Internet through a multitude of mobile devices.

"We expect growing consumer enthusiasm for mobile PC alternatives, such as the iPad and other media tablets, to dramatically slow home mobile PC sales, especially in mature markets," said George Shiffler, a Research Director at Gartner.

The professional market is expected to continue to exhibit double-digit growth in 2011 and 2012, as aging PCs are replaced across all regions of the world.

"However, even in the professional market, media tablets are being considered as PC substitutes, likely at least delaying some PC replacements," said Gartner senior research analyst Raphael Vasquez.

The dramatic rise in the popularity of alternative devices and the limitations of the PC are two of many dynamics that played a significant role in Gartner's revised outlook for the PC industry.