Worldwide PC shipments will grow 12.8% in 2008 to reach 302 million units, according to researcher IDC.

Growth will continue at above 11% in 2009 followed by high single-digit growth through 2012, boosting annual shipments to over 426 million in 2012.

The total value of PC shipments is projected to grow by 7.4% in 2008 to nearly $280 billion. Shipment value will continue to grow by roughly 4% annually from 2009 through 2012, reaching nearly $330 billion by 2012.

Overall volume growth, combined with a steady transition to portable PCs, which generally cost more than desktops, will help offset falling average prices.

"Consumer notebooks continue to drive PC market growth in all regions around the world," says Bob O'Donnell, vice president for clients and displays. "Consumers are increasingly seeing notebooks as essential personal communication and information gathering tools and we expect that will continue to drive growth," he says.

However, the deteriorating economic environment could put a damper on PC growth, says Loren Loverde, director of IDC's worldwide quarterly PC Tracker. However, fourth quarter growth was the fastest since mid 2005 and "we should see continued portable adoption and PC acquisition by both commercial and consumer segments," he says.