I came across this: RDF and the Semantic Web are ludicrous ideas | Semiologic which is a short and thought provoking alternative view of the Semantic Web. I had to post a response, part of which I quote the most important parts here (go visit semiologic to read the rest):
People won't mark up every little bit they put online, but that isn't needed: People will mark up the bits they care about. I'd rather have info that matters marked up than all kinds of fluff.
Companies selling online will mark up their catalogues because 1-2% extra sales for adding some extra processing of their products database is worth it, and it won't take much of an audience to a new product search engine before they'll be able to reach that.
Your example is contrived, because there's no point in marking up everything - you mark up whatever will have it's value increased through markup. That means data that it's important for you that people can find and reason about.
A vast amount of the web HAVE semantic information associated with it in the databases and content management systems they're generated from - but that information is lost when it is output into a form that is only human readable and not easily machine parsable.
Unlock 5-10% of the database content that is tied to the net and we already have the Semantic Web.
Hello again Vidar ;)
As I was replying on my blog, the case here is not so much that the Semantic Web has no use whatsoever. It's that AI-wise, it is not a relevant idea to start with.
This, because the idea that semantic can be thought as something entirely orthogonal to syntax is just silly. Semantic-wise, structured data and unstructured data are equivalent. The only thing that really counts is context.