Guha, I think, has come up with not only a set of compelling applications/use cases, but an easy to deploy tool and simple API (apparently trying to be the GET of HTTP). Simply install the Apache module and place RDF into a directory and you're done. The query API is quite nice too, being able to query by property or by URI if you have one.
In his PowerPoint slides he talks about the TAP vocabulary, using it as a boot strap to turn the existing shared meaning into more shared meaning. The applications discussed are a sidebar for news articles, PeopleNet and Internet WetLab (distributed database with experimental results). That's neat. 5 years away from making money I don't think so.
I think there needs to be a version created so that you can deploy it in Java application servers or as stand alone. This reminds me of the web before search engines. Some sort of automatic discovery system will probably be needed.