According to research firm IDC "spending on virtualization software and services is expected to exceed $15 billion worldwide by 2011, up from $6.5 billion in 2006."
A article in Standard and Poor's predicts huge spending in coming years in the virtualization space. Story covered in Business Week at http://www.businessweek.com/technology/content/nov2007/tc20071130_755713.htm?chan=top+news_top+news+index_technology