Worldwide PC shipments are expected to increase more than 12 percent this year, with shipments of notebooks and ultraportable PCs being the main drivers of this growth, according to a report by research firm IDC.

For 2007, worldwide PC shipments—which include x86 servers, desktops, notebooks and ultraportable PCs—are expected to hit 256.7 million, according to IDC's latest projections, released June 12. That number represents a 1 percent jump from a report IDC released earlier this year.

By 2008, worldwide PC shipments are expected to hit 284.4 million; by 2011, that number is expected to increase to 356.7 million. Desktop shipments, while expected to beat out first-quarter expectations, will continue to decline, especially in the U.S. enterprise market.

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IDC analyst Bob O'Donnell said research found that by the third quarter of this year, the number of notebooks shipped within the United States will surpass desktops–a trend that has already taken hold in Western Europe and Japan.

By 2010, IDC predicts that shipments of notebooks and ultraportable PCs will surpass desktop shipments globally, O'Donnell said. The IDC report found that notebook and ultraportable PC shipments increased 28 percent in the second quarter over last year and that shipments are up 25 percent compared to the prior three quarters.

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"In the U.S., you have a market where there is a desktop-to-notebook conversion trend happening," O'Donnell said. "A lot of the business in any of these mature markets, including the U.S., is a PC replacement market."

Much of the desktop replacement in the United States and other mature markets is being driven by lower prices for ultraportable PCs and laptops and the increase of Wi-Fi and wide-area wireless technology. In emerging markets, IDC found that desktops still make up the majority of PC shipments, although notebook shipments are beginning to increase.

As for the impact of Microsoft's Windows Vista operating systems, O'Donnell said that while the new OS did have an impact in the first quarter of this year, he expects Vista will have less of an impact in the coming quarters.

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Vista adoption will happen but its full impact will not be felt for a number of years. Much of Vista's adoption will wait until enterprise IT administrators figure out how and when they will deploy the new OS across their businesses. What Vista has done so far, O'Donnell said, is increase the average configurations of PCs. For example, most desktops and notebooks now ship with 1GB and 2GB of RAM, compared to the 512MB standard of just a few years ago.

"While you can't ignore Vista, it's not a huge influence," O'Donnell said.

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