The Granular Web consists of services that make web development componentized and outsourceable.

Examples would be using Open ID for identity verification, Rapleaf for trust verification, etc...

The concept, and what is holding it back, is described here at http://www.readwriteweb.com/archives/granular_web.php

Discussion

"Transfer of Assets: Actually in all these services, you don't only transfer the hassles and extra costs, but also transfer the assets that make your site so valuable. In the case of RapLeaf for instance, trust has always been the biggest asset of eBay. That's why eBay prohibited the use of RapLeaf throughout their site. And that's why many web developers may be suspicious about transferring their core assets to RapLeaf, unless they think trust is not a primary asset of their site.

Uncertainty of Services: Site owners are uncertain of the granular services we pointed out above. They can't trust startups and even big established companies like Amazon; because it's obvious that even Amazon may get out of this business if they see no profits and no opportunities. The availability as well is a big question mark for web developers. Because relying on granularity means your visitors will be affected by the outages of the sites you depend on. In the end, in granular dependent sites, even small outages add up successively.

Implementation Threshold: Implementation is often not so easy. Web developers need to learn new patterns and APIs to start experimenting with these services. And considering that the points above create question marks in your mind, would you neglect this threshold or would you keep going?"

Granular Web