Copyfight went somewhat off topic to point out Joshua Porter’s paper on How Content Aggregators Change Navigation and Control of Content at User Interface Engineering. This quote says exactly what I needed:
Every time someone makes a list, be it on a blog […] or a list of groceries, content is aggregated. The act of aggregating content (usually content that is alike in some way) makes it more understandable. Instead of looking at a whole field of information, you choose smaller, more logical subsets of it in the hopes of understanding those. After you’ve done that, you can apply what you’ve learned to the whole, or even just a larger subset.
Why did I need it? It’s all about my working days developing applications for to support academic libraries. The value of a library catalog in the internet age isn’t always in the books (they are valuable, though), but in the taxonomies and metadata that surround them. OPACs are information dense resources that can be used to help select resources that exist in less strict taxonomies (folksonomies, perhaps), and with less detailed metadata.
Yes, Porter’s paper is really about RSS, but parts is parts, right?