Much has been made about the fact that businesses won't be in a hurry to upgrade to Windows Vista. But a report by Forrester Research suggests consumers won't stampede to purchase the new OS (operating system) either.

Forrester analyst Ted Schadler says home users will adopt Vista in much the same way they adopted Windows XP. This goes against the projections Microsoft has made: that Vista will be adopted twice as fast as any other Windows client OS.

"Call us cautious, but we believe that most consumers will tread the path they've been on for years. They buy computers when the old ones break, when the prices come down far enough, or when a lifestyle event triggers the purchase," Schadler wrote in the report. "And that means the best predictor of Windows Vista adoption is Windows XP."

It took more than four years for Windows XP to reach the majority of the PC install base, and it is likely to take Vista the same amount of time, Schadler said.

While he said that Windows Vista does offer certain improvements in security and user interface, none of those "feels disruptive enough to trigger early purchases".

"Therefore, the Windows Vista adoption pattern will look similar to the Windows XP adoption pattern," Schadler wrote.

To improve this rate of adoption of Vista, the report suggests that hardware vendors work with Microsoft to ensure that any PC purchased in the last quarter of the year be ready to run Windows Vista.

Forrester also suggests that Microsoft should ensure there are new applications for Vista that will provide substantial value-add and 'wow' consumers if it wants them to upgrade more quickly.

Windows Vista was released to manufacturers on Wednesday, and will be available to business customers on 30 November. Consumers can buy the new OS from 30 January 2007.