The story from June 2008: http://bits.blogs.nytimes.com/2008/06/25/et-tu-intel/

Intel, the giant chip maker and longtime partner of Microsoft, has decided against upgrading the computers of its own 80,000 employees to Microsoft’s Vista operating system, a person with direct knowledge of the company’s plans said.image

The person, who has been briefed on the situation but requested anonymity because of the sensitivity of Intel’s relationship with Microsoft, said the company made its decision after a lengthy analysis by its internal technology staff of the costs and potential benefits of moving to Windows Vista, which has drawn fire from many customers as a buggy, bloated program that requires costly hardware upgrades to run smoothly.

“This isn’t a matter of dissing Microsoft, but Intel information technology staff just found no compelling case for adopting Vista,” the person said.

The story today: http://arstechnica.com/microsoft/news/2009/10/97-percent-of-intel-testers-recommend-windows-7.ars

Following participation in Microsoft's Technical Adopter Program (TAP), Intel IT found that Windows 7 running on PCs with Intel vPro technology delivers the best productivity for our employees & the best managed solution for IT. After three months of trial with over 300 users, 97 percent of our test users would recommend the new OS to peers and Intel IT sees the potential to save $11M over the next three years. Because of improved employee productivity, reduced costs, ease of deployment and enhanced security, Intel IT is rolling out Windows 7 to early adopters this year and enterprise deployments starting early 2010. Authored by John Gonzalez (OS Product Line Manager, Intel IT), this paper describes these benefits and results of Intel's participation in the Windows 7 TAP.

In addition to the 97 percent statistic, Intel listed four other key results:

•Performance: More responsive for key tasks such as booting and launching productivity applications.

•Stability: Fewer users experienced blue screens.

•Application Readiness: No remediation required during evaluation; application readiness does not appear to be a roadblock to adoption.

•Total Cost of Ownership: Initial estimate of potential USD 11 million net present value.