In the first post you quoted I linked his book to it, which included a summary of those results. Here's a bit more info on it:
http://timgroseclose.com/about-left-turn/
Beyond that I guess you can find whatever you're looking for on Google
Part of this research actually confirms what you're saying - the media isn't as liberal as portrayed by the people most frequently using the term, i.e. conservative opinion leaders. And that the extremes aren't well covered on either side. Here's a comment of his about the NYT:
To give you an idea of the scoring system, here's some reference points he mentioned:
I think it's worth looking into. The fact it uses how people vote on particular issues does have its issues, but it removes a lot of the opinion and removes the bias of our own analysis seen through the prism or our own particular political leanings.
Thanks, I’ll be interested to read this because from the perspective I have, the US media has a very right slant on things but I guess that could be because my spectrum is a lot further left than the US so it’s perfectly feasible that what I view as centrist is “liberal”.