Two brains for the price of one. That is the formula Microsoft has hit upon to try to make up for the loss of Bill Gates' guiding hand on its technology direction.

Their ability to navigate one of the computing industry's periodic upheavals - with the focus shifting from desktop PCs to the web - will determine whether Microsoft remains at the forefront of the industry Mr Gates did much to shape or instead slips into increasing irrelevance.

Ray Ozzie, a renowned software developer and originator of the groundbreaking Lotus Notes, was lured to Microsoft three years ago as Mr Gates cast around for a successor. He has taken over the title of chief software architect, with control over Microsoft's technical direction as far out as five years.

For the longer-term vision and the management of its research labs, Mr Gates has turned to Craig Mundie, a cerebral supercomputer engineer who came to Microsoft through an acquisition 16 years ago and has played a central role handling its relations with government customers globally.

The vision they share is one that appears to go against the orthodoxy of the times. The technology world is buzzing about the shift to "cloud-based" services, where software delivered over the internet - like Google's online word processor - may one day replace the need for software running on "client" machines such as PCs and handsets.

"We thought deeply about that and decided no," says Mr Mundie. "We tend to believe that there will continue to accrue a large amount of computational capability in the literally billions of intelligent gadgets and devices." The opportunity for Microsoft over the next two decades, he says, lies in planting the software on these billions of devices, co-ordinating them and linking them to a "services layer" of intelligence supplied from the "cloud".

According to Microsoft technologists, this clash of visions is more a question of rhetoric than any profound technical disagreement.

"Every major services vendor, every single one of them that has started with a services focus is moving to software," claims Mr Ozzie. "So they're just coming to the same endgame."

If "software plus services" is the mantra at Microsoft as it looks forward to life after Mr Gates, another issue seems less clear-cut: What role is there for hardware? Through the Xbox games console, Microsoft has discovered the advantages of "wrapping" software in hardware.

"I do believe in end-to-end design, conceptualisation and design of hardware, software services," says Mr Ozzie. He adds, though, that Microsoft will have more impact planting its software in the many devices created by other companies.