Your getting into really far out AI type domain. I have done extensive work in text transformation into machine knowledge mainly using Attempto Controlled English (see: http://attempto.ifi.uzh.ch/site/), it is a natural language (english) that is completely computer processable into several different ontologies, such as OWLDL.
Seems like that would we way overkill though...
Is there a reason for not just taking the first few sentences of your blog post and then appending an ellipse for your summary?
