Computer shipments to retailers are estimated to end the year much lower as consumers spend more time on smartphones and tablets.
Shipments of desktops and laptops (whether they run on Windows, Mac or other operating systems) are expected to show a decline of more than 10 percent, the most dramatic drop ever, according to research firm IDC. Shipments dropped about 4 percent last year.
"It's like newspaper subscriptions," said CNET Editor-in-Chief Paul Sloan. "They're just going to keep going down. Mobile is growing; tablets are growing."
Although no tablet on the market can entirely replace a personal computer, he said, the ones available are fine for what most users do with them.
"They're watching movies, they're on the Web, they're using Facebook ... and that doesn't require a full-fledged keyboard," Sloan said.
Separately, he said, Microsoft is rumored to be working on a software update to help tie together tis Windows, Windows Phone and Xbox software, possibly in the hope of drawing Xbox users to other Microsoft products.
(Read More: Expect revenue to stabilize in 2014: HP's Whitman)
"If you have users used to Xbox who suddenly have a very similar experience on another device and you can somehow parlay that uniformity to get people to buy Windows Phones, great," Sloan said, adding that it's difficult to get smartphone users to switch operating systems.
Microsoft told CNBC that it doesn't comment on rumors.
—By CNBC's Althea Chang