Interesting questions. I believe the liberal press went after the story because of pent up frustrations about not going after Clinton. In other words, Condit became a whipping boy for Clinton.
As to why everyone else is following this, I believe the whole thing is the stuff of intrigue like Dianna's death. It may be an added bonus that he is a RAT. Personally I like to follow it but I think the evidence against Condit is pretty thin and I would not vote to convict him if I were a juror.