A lot is riding on Windows XP (which stands for experience). The Microsoft spin is that users will enjoy a new experience in computing with this product, which took four years to develop at a cost of US$1 billion, making it the largest software project ever.
And what does the corporation hope to reap in return for pumping so much time and money into a single software item?
Promoting it as the biggest milestone since Windows came into being, Mr Gates is clearly hoping the supposedly easy-to-use operating system will lure newcomers to the world of computers, reverse a slump in PC sales, and increase profits for the world's largest software company.
"What it takes to drive growth is new experiences, letting people do things they couldn't do before," Mr Gates told the large gathering invited for a sneak preview of Windows XP at the Experience Music Project - Seattle's new rock n' roll museum built by Microsoft co-founder Paul Allen.
A global publicity blitz is planned to promote the product. "We'll spend whatever it takes," vowed Microsoft executive Greg Sullivan.
But many industry analysts say it is far from certain that consumers will rush out in droves to buy Windows XP either as an upgrade or to power a new PC. What is even less clear is how interested businesses will be in switching over to the new system.
"It's not a revolutionary change," said Bob O'Donnell, a research director with IDC in Silicon Valley. He sees Windows XP as containing "a whole bunch of new little things" rather than representing a paradigm shift.
"Is that enough for people to go out and buy it? I really don't know," he said.
This question mark extends to Asia where PC sales growth is much stronger but where home and office computer penetration is less than half of that in the United States. Windows XP may interest those in Asia who already own a PC or plan to buy one but it is unlikely to influence the reasons - economic or otherwise - why computer penetration remains low.
"If people cannot afford to buy it, they won't. Windows XP cannot change that," Mr O'Donnell said. But he believes the story is totally different for gadget-crazy and wealthy Asian markets like Hong Kong or Japan.
"For them this is great," he said, pointing to the new operating system's streamlined features for easy interaction with devices such as digital cameras and cell phones.
One reason why many are unsure if Windows XP will spur new PC sales in the US is the already very high computer penetration of 60 per cent.
"Microsoft wants to push PC penetration in the home but there is a fair bit of resistence beyond that level," said Jonathan Geurkink, a software analyst with Ragen MacKenzie.
Mr Geurkink believes Windows XP - available by the end of the year - will help stimulate PC sales but only over a period of time. "It won't be an overnight phenomenon," he said.
But with Microsoft clearly intending to make Windows XP a key part of its new .Net strategy - which Mr Gates has said will revolutionise the Internet - much of the company's attention is likely to turn to making it a core product which will help streamline the firm's operations.
If Wall Street was impressed with the latest Microsoft wizardry it did not show it. The company's shares closed down 56 US cents after the unveiling.
