The software giant said Office 2010 was available at more than 35,000 retail stores around the world, from online retailers such as Amazon.com, or for download through Office.com.
Microsoft hosted a launch event in Sydney's Martin Place yesterday, giving away 110 copies of the new software suite to members of the social-networking site Foursquare.
Entrants at yesterday's Office Mayor Meet-Up had to prove that they were the mayor of at least one location to score a copy of Office 2010. Foursquare mayor of Sydney CBD, George Gorman was first in line at the Microsoft event.
Office 2010 has also been preloaded on desktops and laptops from Acer, Asus, Dell, Hewlett-Packard, Lenovo, Samsung and Sony, and Microsoft said it expects more than 100 million PCs to ship in the next year equipped with the software.
The software features updates to the ubiquitous spreadsheet, email, presentation and word processing programs (Excel, Outlook, PowerPoint and Word) used by tens of millions of businesses.
Microsoft, citing comScore data, said more than 1 billion PCs worldwide have installed Office software, making it the most widely used productivity suite.
The latest edition of Office includes a web-hosted version aimed at countering competition from emerging "cloud" products offered by Google.
For the new version of Office, the first since 2007, Microsoft is offering Office Web Apps — online versions of its most popular products that work directly in a web browser and are hosted on servers in the "cloud" instead of on personal computers.
The move is seen as a response to the challenge posed by Google and others offering free online cloud-computing programs.
The top-of-the-line version of Office costs $849, while the Office Home and Student version is priced at $209, and $379 for Office Home and Business. Google Apps is free to individual users while businesses are charged US$50 per user, per year.
Microsoft said Office 2010 was available on Tuesday in 10 languages and would be available in 94 languages over the next few months.