"Linux servers posted their ninth consecutive quarter of double-digit growth with year-over-year revenue growth of 42.6 percent growth and unit shipments increasing 31.7 percent, according to IDC's findings. Revenues for Windows servers grew 13.3 percent, unit shipments were up 19.1 percent year over year. Quarterly revenue of $3.9 billion for Windows servers represented 33.9% of overall quarterly factory revenue, equal in size to the Unix market."

Now wonder Microsoft sees Linux as a threat in the server market so much - revenue growth for the OS was at almost 43 percent in the third quarter of this year, contrasting with Windows' lower figure of 13 percent. The global server market remains a healthy place, with revenues climbing 5.5 percent in the past year to $11.5 billion in the third quarter of this year. This is the sixth such consecutive quarter of positive revenue growth.