There is an interesting article at titled: Structured data is boring and useless.. This article provides insight into a serious point of confusion about what exactly is structured vs. unstructured data. Here is a key excerpt:
"We all know that structured data is boring and useless; while unstructured data is sexy and chock full of value. Well, only up to a point, Lord Copper. Genuinely unstructured data can be a real nuisance - imagine extracting the return address from an unstructured letter, without letterhead and any of the formatting usually applied to letters. A letter may be thought of as unstructured data, but most business letters are, in fact, highly-structured." ....
Duncan Pauly, founder and chief technology officer of Coppereye add's eloquent insight to the conversation:
"The labels "structured data" and "unstructured data" are often used ambiguously by different interest groups; and often used lazily to cover multiple distinct aspects of the issue. In reality, there are at least three orthogonal aspects to structure:
    * The structure of the data itself.
    * The structure of the container that hosts the data.
    * The structure of the access method used to access the data.
These three dimensions are largely independent and one does not need to imply another. For example, it is absolutely feasible and reasonable to store unstructured data in a structured database container and access it by unstructured search mechanisms."

Data understanding and appreciation is dwindling at a time when the reverse should be happening. We are supposed to be in the throws of the "Information Age", but for some reason this appears to have no correlation with data and "data access" in the minds of many -- as reflected in the broad contradictory positions taken re. unstructured data vs structured data, structured is boring and useless while unstructured is useful and sexy....

The difference between "Structured Containers" and "Structured Data" are clearly misunderstood by most (an unfortunate fact).

For instance all DBMS products are "Structured Containers" aligned to one or more data models (typically one). These products have been limited by proprietary data access APIs and underlying data model specificity when used in the "Open-world" model that is at the core of the World Wide Web. This confusion also carries over to the misconception that Web 2.0 and the Semantic/Data Web are mutually exclusive.

But things are changing fast, and the concept of multi-model DBMS products is beginning to crystalize. On our part, we have finally released the long promised "OpenLink Data Spaces" application layer that has been developed using our Virtuoso Universal Server. We have structured unified storage containment exposed to the data web cloud via endpoints for querying or accessing data using a variety of mechanisms that include; GData, OpenSearch, SPARQL, XQuery/XPath, SQL etc..

To be continued....