I’m not going to get involved in speculating about Libby’s guilt or innocence, but these two articles point to the central role of reporters in the case against him. This has two consequences, both problematical for the profession of journalism.
First, any decent defense attorney is going to work pretty hard to impeach the reporters as witnesses, which means putting their careers under a microscope. It’s hard to imagine anyone emerging from such scrutiny unscathed. And it’s hard to imagine these three (Tim Russert, Matthew Cooper, and Judith Miller) not serving as stand-ins for their respective news media (television, news magazines, and newspapers), at least in the public mind (to the extent, of course, that anyone pays attention to this).
Second, once these three testify against Libby, any source is going to think twice about promises of confidentiality and about speaking to journalists in anything other than the most bland and innocuous manner. News-gathering will get more difficult, and the people who are willing to say "interesting" things may be different from those who actually have "interesting" things to say.
Update: Theres more along roughly the same lines here.