Microsoft took the wraps off Windows 7 in a series of launch events, headlined by its chief executive Steve Ballmer in New York. Similar events were held in Beijing, Tokyo, Hamburg and Munich.
"At the end of the day, it's trying to make the everyday usage of the PC better in the way you want it to ... simpler, faster, more responsive, less busy," Ballmer said.
Despite the global push, this has been a relatively low-key launch fitting the way Microsoft is characterising the new OS - feature-rich, but above all, straightforward to use.
The Vista OS, plagued by a variety of issues including hardware compatibility problems, slow performance and system alerts, was not always embraced by Microsoft customers.
The older Windows XP still is used by 72 percent of computer users, compared to 19 percent for Vista, according to the latest Market Share Report by web-site software company Net Applications.
One crucial difference between the making of Windows 7 and Vista - bringing in manufacturers very early in the development process to create metrics for testing - began three years ago, stressed Microsoft and PC company officials at the launch.
"What's special about Windows 7 and the way it came together was ... an intense collaboration with hardware and peripheral makers, developers and customers around the world," Ballmer said.
"We engaged early, there was early testing with Microsoft, working on metrics ... taking a humble approach toward really nailing the fundamentals - boot time, resume, suspend," said Michelle Pearcy, director of worldwide consumer marketing for Dell. The result is a product that is "fast, efficient and fun," she said.
Businesses have had a chance to be early adopters since August, so the hoopla accompanying the worldwide launch is mainly aimed at consumers, noted Tami Reller, chief financial officer and corporate vice president for the Windows Business Group.
That was the case in New York. Ballmer and corporate vice president Brad Brooks, who demonstrated the new OS, focused on the consumer experience. Brooks showed how users could import images from a camera into Windows Live Movie Maker to make slide shows with a short series of clicks.
The demo also showed off Windows 7 MultiTouch features, which let users move objects around the screen by touching them and dragging with their fingers.
Windows 7 is a "touch platform," said Ballmer, who added that he expected developers to build a wide variety of touch applications.
A high point of Brooks' demo was the HomeGroup feature, which allows users to share music, pictures, printers and documents across PCs. At one point, Brooks showed how he could control multimedia content across 16 different device screens including TVs, desktop PCs, laptops and netbooks.
While most consumers who bought new PCs over the past few years automatically got Vista pre-installed on their machines, corporations were offered a "downgrade" option on new machines if they wanted to stick to XP - and most business users never migrated to Vista. These millions of users still on XP represent a big target.
"On the business side there's still a lot of XP and there's a real opportunity to bring the value of Windows 7 to businesses, saving tremendous IT costs," said Reller.
There are, for example, more controls for IT departments to manage security and software downloads. "We're saving well over a hundred dollars per desktop in the management piece alone," Reller said.
Despite Microsoft's hopes for quick migration, however, many analysts have downplayed prospects of immediate take-up by large corporations.
"The Windows 7 release will generate renewed interest in hardware upgrades in consumers and small businesses following its release, but corporate demand is not expected to gain momentum until the end of 2010," said Charles Smulders, managing vice president for Gartner.
"An overdue PC hardware upgrade cycle, and the economic environment, will be as equally important as Windows 7 in determining final demand in 2010."
In the UK, retailers reported that Windows 7 pre-order sales had become Amazon's largest-grossing pre-order product ever, outpacing previous pre-orders for the Nintendo Wii and Harry Potter. Retailer DSGi reported that it sold more Windows 7 copies during three weeks of taking pre-orders than copies of Windows Vista over the entire first year that OS was out.