[onuryavuz]

I see. Trying to detect keywords in an article could be nice improvement.

Another question, why did you limit the lower bound for the score w/ 200 ?

I assume you start indexing the HN submissions. In the long run you can create a context aware version of HN, e.g. 'Bring HN submissions with keyword X submitted during the last week.' This could be a brand new way to browse HN.