Netbooks are also reaching buyers in new ways, which could boost their shipment numbers. They are being offered as part of telecommunication bundles to consumers in Europe, for example. That trend has already started to appear in the U.S., with the Acer Aspire One being offered by RadioShack for US$99.99 with a two-year AT&T mobile broadband plan.

Netbooks helped Acer record a 25.3 percent growth in its worldwide PC shipments during the fourth quarter, Bell said. By contrast, top vendors Hewlett-Packard and Dell struggled to record solid growth. HP shipped 15 million PCs in the fourth quarter, a 3.1 percent year-over-year gain, to give it 19.6 percent market share. Dell saw its shipments fall year-over-year by 6.3 percent to 10.6 million. Acer's shipments were 9.1 million, followed by Lenovo, which saw a 4.8 percent drop in shipments to 5.6 million. Toshiba saw its shipments climb 20.2 percent to 3.7 million for fifth place.

Acer's growth was particularly strong in the U.S., where shipments jumped 55 percent in the fourth quarter, increasing its lead over Apple as the third-largest PC vendor, according to Gartner.

Acer shipped 2.38 million PCs in the U.S., while Apple's sales increased 8 percent year-over-year to 1.26 million units. Dell and HP, the top two PC vendors in the U.S., saw their sales decline. Dell's shipments fell by 16.4 percent to 4.47 million units, giving it 28.6 percent of the market. In close second, HP saw its shipments drop 3.4 percent to 4.3 million. Toshiba came in fifth place.