More users are starting to evaluate and deploy Windows Vista, but they are showing more concern over perceived performance and patching improvements and the operating system's hardware requirements, according to a recent study.

Nearly 30 percent of respondents have begun to use or evaluate Vista since it shipped in November 2006 to corporate users, according to a study, conducted by researcher Walker Information on behalf of IT services and product supplier CDW.

The Vista Tracking Poll was the second conducted by Walker for CDW and is available for free (registration required). An identical survey was done last November.

The poll shows that 87 percent of 753 IT decision-maker respondents plan to eventually adopt Vista. It also found an 8 percent increase over the first poll in terms of deployments and evaluations of Vista by corporate users.

Since the first survey, 1 percent of users had completed Vista implementations and another 19 percent planned to complete their implementations in the next 12 months.

The survey also found that 6 percent of organisations are implementing Vista on a schedule that extends beyond 12 months, while 13 percent plan to start their implementations in the next year. Another 13% said they have no plans to upgrade.

"I don't think we were surprised by any of the data," says JoEllen Amato-Tuck, Microsoft brand manager for CDW. "It seems to be in line with what the first survey showed."

The second survey revealed that user concerns over hardware requirements being too excessive rose 9 percent over the first survey, from 28 percent to 37 percent. It was the fourth most common concern. The first was the expectation of bugs in the first Vista release.

A further 18 percent of users said they would need to upgrade 91 percent to 100 percent of their Windows-based hardware for it to be Vista compatible, a 2 percent increase over the first survey. Also, concerns that the benefits of adopting Vista are not clear enough rose 6 percent from 32 percent to 38 percent.

The concern that showed the steepest decline was having enough money to pay for a migration, which fell from 30 percent to 25 percent. Only 5 percent of respondents in the second survey said they had no concerns about Vista, down from 6 percent in the first survey.

The company plans a third survey sometime between September and December. CDW says the tracking poll will show over time how evaluation variables and deployment strategies are progressing.

The top benefit in both polls was improved security with 78 percent of respondents citing that feature. But the second poll showed that fewer respondents think Vista's performance and patching represent improvements in the software.

Positive perception of performance as a key benefit was down 7 percent from 63 percent to 56 percent. Patching fell from 31 percent to 25 percent and Windows Update from 36 percent to 30 percent.