Microsoft published a IDC worldwide research study, which explores the business value and return on investment (ROI) of Windows 7 for small and midsize businesses.
"IDC's research team conducted qualitative case study interviews, quantitative end user and IT manager surveys, and used an ROI model for Win7 deployment to generate their results. Through the Win7 ROI analysis and end-user survey, research showed Win7 deployment resulted in positive changes in all measured categories, ultimately saving businesses time and money.
Researchers found the payback to companies started just after seven months and a return on investment of 375%. It showed that each user saves an average of about 43 hours, or $1,400 total benefit per PC, annually."
More Info: White Paper