A big YES for the Semantic Desktop comes from the Desktop Developers Conference.
I wasn’t there but Edd Dumbll blogged very good.
My bit is: Edd talks the same language as we do. RDF.
The gnowsis Semantic Desktop project we do right now at the DFKI.de is nearly what he means. We represent all “user-interesting objects” in a BIG rdf graph. And that is built dynamically, by extracting the data from the different applications.
Ontologies like FOAF, DC and VCARD are spread all over our system and make it easy to annotate photos and so. We are working night and day now to make a release soon, as I see that our thing is definitely interesting for the rest of the world.
Expect a gnowsis release in September.
in the meantime, read my thesis