The root of your problem would be in identifying what the topics of a given thread/node are.

Assuming you don't want to hire a team of helper monkeys to classify every node in to a Taxonomy, then you would need to look into some of the many attempts at classification of documents by programmitic analysis. This comes up about once a year on slashdot in the form of a "has anymore found a good way to categorize all of your email?" question ... there seem to be some decent algorithms out there for doing classification, but many of them require a predefined list of categories with sample sets.

I've heard of systems that can find common topics among large quantities of text, but i've never really looked into it in depth.

In reply to Re: Tracking popularity of Perl discussion topics by hossman
in thread Tracking popularity of Perl discussion topics by allolex

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