Sales of Office software are a mainstay of Microsoft. The Office division has earned profits of over $9 billion in the first three quarters of fiscal year 2009, on sales of $14.3 billion.

Office will start being added to Finnish company Nokia's E-series line of business 'smart phones' in 2010 and could later be brought to other phones, Oistamo said.

Microsoft has said that Office 2010 documents have the ability to be displayed on a variety of mobile phones, expanding the company's reach from the traditional PC market to the Internet and mobile devices.