Various companies such as Google use Linux desktops instead of Windows (according to ZDNet). According to TechReublic other big names that use it are NASA, the French military police, CERN (which is also known as the European Organization for Nuclear Research) and the U.S. Department of Defense. While an estimated 1.5% of desktops use Linux, it is a good choice for staying safe from viruses and spyware.
Another case for using Linux is that employees can benefit from the experience with an increase in earning potential. See this article for more information.
Development in a Windows environment is not like Linux. As a best practice in Linux, running things as administrator should be done on an ad hoc basis. Some people who develop in Windows recommend that Visual Studios always be run as administrator. To learn more about this, see this link.
Should more people use Linux for everyday tasks and/or software development? What is your opinion?