I've been writing code to do things in this area since 1999. I wrote a RSS parser in Delphi in '99, was in the RSS/RDF/Atom wars, wrote a aggregator with Bayesian filtering in 2003, and I'm one of the authors of the ROME Jave RSS library. I'm currently running a research project in news event prediction and detection.

I don't think anyone wants bias detection.. or maybe they do so that they can only read things that they agree with?