One thing that becomes clear when you consider the exhaustive coverage of Yahoo's business model and related technology infrastructure is that Yahoo—like Google, Microsoft and a host of other Web service providers—has its heart set on being a platform.

In the old days, the platform was first the operating systems on the client machine and later the servers. But the Web has changed that, and companies as big as Microsoft and as small as Salesforce.com are all now trying to recruit developers to create applications that can be delivered via their platforms in the network cloud.

As Dave Carr explains in this issue's cover package, Yahoo is wooing developers to create applications that will run across its network, which it also refers to as a platform. Google, Microsoft, eBay and others have similarly made development kits available that essentially expose an application programming interface (API) to just about anyone who wants to create an application.

The intriguing question this raises for any IT organization at any company with any kind of business- to-consumer model is which, if any, of these organizations will have enough pull to require their companies to see them as full-fledged routes to markets.

Already it's plain to see that the major Web sites are becoming networks through which third parties are distributing content, software and services. As this trend continues, the more inevitable it becomes that businesses of all shapes and sizes will need access to developers familiar with the different Web environments to ensure that their offerings don't get lost amid the thousands of other services that will be offered through the various clouds.

Of course, it's tempting to say, who needs to be in someone else's cloud; all you need is a good Web site backed by solid search engine optimization. But even on the Web there is a cost of sales, and just as in real life, you have to bring your products and services to your potential customers— you can't wait for them to come to you.

In effect, Yahoo, like other sites such as Amazon and eBay, is little more than the 21st century version of the local strip mall. It isn't pretty, but everybody goes there. So if your presence on the Web is down the digital equivalent of a side street, you can expect to fall victim to the same location issues that bedevil every brick-and-mortar retailer that's not on the main drag.

It will be interesting to see how long it will take for many conventional businesses to figure this out and respond. When you visit a Macy's store, for instance, you find essentially a building full of designer boutiques organized by brand. An e-commerce Web site is pretty much the same.

So maybe Macy's needs to develop and promote an API for its Web site that would make it easier for more vendors to get into the Macy'sanchored online mall. After all, why should Macy's be limited online to the same products it essentially resells in its stores on behalf of other companies?

And while Macy's is at it, it might also provide some compelling content designed to draw people into its online mall in the first place.

Whatever happens ultimately, it's clear we're on the cusp of a major shift in the definition of the term platform as it applies to computing. In fact, about the only thing left to decide now is how proactive your organization must be to deal with that shift.

But to one degree or another, the transition to network clouds as platforms is going to change not only how your organization thinks about IT but how your company as a whole takes its goods and services to market.