Despite being on a sales pace that would make it Microsoft's best selling operating system in history, only a small percentage of consumers plan to upgrade their computers to Windows Vista this year, according to a new poll.

When asked: "Do you plan to switch or upgrade your primary home computer to Windows Vista ... in the next 12 months?", only 12% of 2,223 Internet users surveyed by Harris Interactive responded in the affirmative. 67% said no, while 20% said they weren't sure.

The survey results were released Thursday.

A lack of consumer faith in Microsoft's promises that Windows Vista will significantly improve their computing experience is what's behind the low numbers, said Milton Ellis, VP of Harris' Technology Group. "Vista promised better performance, reliability, security, and a revolutionary interface, but it appears consumers looking to upgrade are not ready to buy into the promise," said Ellis in a statement.

The poll results notwithstanding, Microsoft has said Windows Vista sales have been strong out of the gate. The company recently noted that total sales of Windows Vista licenses in February -- the OS's first full month of availability -- topped 20 million.

By contrast, Windows XP, the predecessor to Windows Vista, sold only 17 million licenses in its first two months on the market in 2001, Microsoft said.