When Microsoft announced .Net, Bill Gates called it a "bet the company thing".

READER ROI

• What .Net really means for CIOs
• Why Web services standards will transform the CIO's job
• How to operationalize Web services

But in the process of becoming far less than Microsoft had dreamed, .Net has become much more than CIOs had hoped for and is pointing the way to a new definition of the CIO role, creating a world in which vendors - including Microsoft - matter less and less.

Four years ago, CIOs worried that .Net, which Microsoft was proclaiming a revolutionary new software architecture, was just another name for lock-in. "I'm not confident that Microsoft .Net will be compliant with open standards," Brett Kottman, then the e-commerce director for Excellence in Motivation, told CIO (US) in 2001.

He wasn't alone. In a CIO Research Report from that year, seven out of 10 CIOs said they wouldn't adopt .Net. Just one in four said Microsoft's motivation for launching .Net was technical; almost 60 percent said the motivation was marketing.

Fast-forward to earlier this year when FedEx executive VP and CIO Rob Carter built a Web service that allows his people to print to a nearby FedEx Kinko's from inside Windows Office applications. He used .Net to build it. But here's the surprising part: On the back end, the platform it connects to is not Windows and, says Carter, "It's really of no consequence that it's not."

But Windows has never connected easily to anything but Windows. Nor, for that matter, has any vendor's software easily linked with anyone else's. Indeed, CIOs used to be defined by which technology architecture they bet on, and the software business used to be defined by which vendors got CIOs to bet on their stuff. As Rick Berk, the CIO of private bank Brown Brothers Harriman, puts it: "Vendors have always created things to pin us down."

So how can Carter be so casual about mixing architectures when that's always been excruciatingly complex and expensive and therefore ill-advised? What happened to lock-in?

Web services standards happened. If your native tongue is .Net or J2EE, C# or Java, WebLogic or WebSphere, Windows or Linux, or anything else, all countries are starting to communicate using the lingua franca of XML and associated specs like UDDI, WSDL and SOAP. And so far, software vendors have adhered to those standards in their products, including Microsoft with .Net.

After decades of holding customers captive inside the walls of proprietary software, Microsoft and its competitors are selling products such as .Net that help tear down those walls. Why?

The answer is, the market made them do it.