Microsoft plans to take a swipe at Google when it opens access to its MSN and other public Web sites to let developers assemble new applications that build on those sites. Microsoft will publish the application programming interfaces to some of its public Web sites, easily allowing developers to program for them. There will also be better tools to write those applications. The company will detail this "Web platform" strategy at the forthcoming Developers Conference in Los Angeles in just a few days time.

These are intended to open up the world of Web 2.0, where new applications are built using pieces of existing, public Web sites. Web sites stop becoming so much like Web sites as more development platforms. Third-party developers can write applications that tap into the power of say, Google maps, or some powerful MSN service.

Microsoft has already given developers access to some of its Web sites. MapPoint, for example, has had a Web services interface for a few years. But the company is ramping up efforts to make its Web sites programmable and customizable by end users, mirroring the strategies at Google, Yahoo,, eBay and a growing number of Web sites.