Quoting from the SWsoft official announcement:
Operating system virtualization software Virtuozzo from SWsoft is growing fastest among all vendors — 98 percent — in the hot overall market for virtualization technology, according to industry analyst firm IDC. The worldwide industry sales of virtualization software experienced a 67 percent growth rate from 2004 to 2005 ?- with revenues topping $560 million.
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According to IDC, the virtualization market is expected to grow to $15 billion worldwide by 2009.
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The IDC report also showed virtualization implementations on Linux experienced the fastest growth from 2004 to 2005 continuing the trend from the previous year. That trend is expected to continue through 2009…
Check the original IDC report: Worldwide Virtual Machine Software 2005 Vendor Shares, September 2006.