I just listened to a talk by Brian O'Leary called "Context first: A unified theory of publishing"(http://vimeo.com/20179653). In the talk O'Leary posits that the thing killing the publishing industry is something he calls the container model. Publishers, and authors, think of content in terms of the container it is intended to fill and in doing so leave the content's metadata, its context, on the table. A newspaper company, and its writers, think of the content the generate as articles that live in a single edition of the news paper. All of the context that links an article to other articles in time and space is lost. When the article goes on-line, there is an attempt to recreate the context, but it is never going to recreate the full context. The paradigm needs to shift so that context is a primary consideration when creating content. Modern customers live in a world of content abundance and thus do not value content as much as they value services that make content discovery easy.
What does this have to do with technical writing? A lot. A large chunk of what technical writers do is make information accessible and discoverable. If we primarily think in terms of books, articles, help systems, topics, etc. then we run the risk of forgetting how each chunk of information fits into the whole and making that clear. We also forget to add the metadata needed to make the content easily discoverable. It is the indexing argument for the digital age. Authors put the indexing off until the end and usually end up with less than ideal indexes or none at all. Now we skip the indexes because everyone uses search to discover content, but we don't add any of the metadata to make the content search better. We leave it up to full text search to pluck words off the page or title searches.
Thinking about content as part of a whole and adding metadata to improve content discovery are key parts of a modern digital technical library. It is also value that requires specific skills to create. Indexing is hard and so is tagging.