Danny Ayers comments on an anti-RDF piece by Sean McGrath, saying it is "trival to debunk." I don't think his concerns can be tossed aside so easily.
There is a lot of truth in what Sean is saying. I don't think he's really saying that there's anything wrong with RDF itself, but suggesting instead that since it is an abstraction (such an abstraction) it has significant barriers to entry and use.
Also, I don't think you can put people's willingness to use programmatic abstractions and data abstractions into the same box. Especially in a situation where people imagine that the data abstractions are only a few short steps from being a human communication medium.
This is related to what I was trying to say over on the collab lists.
A tool like RDF is hard to use because its uses are abstract rather than concrete. You can't walk up to it and comprehend, in short order, what it is for. Nor is it particularly easy to try so the sort of clear breakdown that would lead to a present-at-hand moment doesn't happen so the real goal, where use is ready-to-hand, doesn't happen either.