Microsoft formally launched Windows Vista and Office 2007 at a company event in New York.
Chief executive Steve Ballmer made the announcement that the products were shipping worldwide to volume-licence business customers at an event held in Times Square at the NASDAQ MarketSite.
The launch marks the first time Microsoft has launched new versions of Windows and Office on the same date since Windows 95 and Office 95 were launched 11 years ago.
"It’s an incredible step forward for business computing in a year of unprecedented innovation from Microsoft," said Ballmer.
"These are game-changing products."
The Microsoft chief said that during the testing of both products, over 5 million copies of the beta had been distributed worldwide, and that Microsoft collected data from more than a billion user sessions. Ballmer said he expects that over 200 million people will be using one or both of the products by the end of 2007.
Both Vista and Office 2007 are slated for consumer availability on 30 January.
Along with Vista and Office, Ballmer also released 30 new business products, including Exchange Server 2007 and Office Project Server 2007.
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