The competition for Microsoft is continuously growing and it is coming from more sources than just Google. Virtual Server 2005 is a popular application that Microsoft released to allow users to put a server OS on top of another operating system. VMWare is competing with Microsoft by releasing their version of Virtual Server, dubbed VMWare GSX, for free! VMWare is a very popular company that has been in the virtual operating systems business for quite some time now. This is a very prominent move on their part.
News Source: Bink.nu