Real-time discourse analysis using relative frequencies might be an interesting feature to add, but hard to implement (I think).

But really your main goal of viewing clusters around frequently used terms would really benefit from an extra level of linguistic abstraction: defining topic groups (e.g. word fields) and semantic/ontological domain marking. It is more interesting to see what themes occur than what specific words. If you had an ontology, you could see a broader picture.

The topic groups feature would be easier to define. You just need to define fields of related words (e.g. nation, people, folks, public; terrorist, evildoer, enemy). That would be pretty cool.

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Allolex