Windows 7 will become the leading operating system used in PCs worldwide by the end of 2011, running on 42 per cent of all computers.
According to research firm Gartner, 94 per cent of new PCs will be shipped with Windows 7 in 2011.
Annette Jump, research director at Gartner, said uptake of Windows 7 will be fastest in the US and Asia-Pacific, but western Europe may lag behind.
"The economic uncertainties in western Europe, political instability in selected Middle East and African countries and the economic slowdown in Japan after the earthquake and tsunami in March will likely lead to slightly late and slow deployment for Windows 7 across those regions," she said.
Gartner's forecast assumes that Windows 7 is likely to be the last version of the Microsoft OS to be deployed to everybody in the form of large, corporate-wide migrations.
In the future, many organisations will also use alternative client computing architectures for standard PCs with Windows OS, and move towards virtualisation and cloud computing over the next five years.