I'm not saying that the story was completely ignored because I found a link to it, as did you. However, compare the number of times the story gets reported about each of the justices. One explaination for the difference is quite likely bias. The New York Times op-ed you linked contained a couple paragraphs:

The swelling controversy has exposed other less egregious but still troubling outside activities by Justice Scalia. The Los Angeles Times recently reported that he delivered a speech to a $150-a-plate dinner of an anti-gay advocacy group in Philadelphia even as the Supreme Court was deliberating in the Texas sodomy case last year.

This problem is not Justice Scalia's alone. On the other side of the court's ideological spectrum, as another L.A. Times article noted, Justice Ruth Bader Ginsburg maintains involvement in a lecture series named for her that is co-sponsored by New York City's bar association and the NOW Legal Defense and Education Fund, which frequently participates in Supreme Court cases. Justice Ginsburg is relatively circumspect in her public remarks, but it's still unwise for her to retain an ongoing affiliation with such an active advocacy and litigation group.

The interesting point about that second LA Times article is that it was a blogger who goaded the LA Times into reporting it. When they released the first article about Scalia, they never even thought to consider if liberal justices were doing the same thing. To their credit, when the blogger pointed out the truth to them, the LA Times did report the story. However, thorough reporters would've tried for more balanced coverage in the first place.

NOW very often has issues before the Supreme Court. Ginsberg didn't just do a one time thing with NOW but, as the article I linked stated, "Supreme Court Justice Ruth Bader Ginsburg has lent her name and presence to a lecture series co-sponsored by the liberal NOW Legal Defense and Education Fund, an advocacy group that often argues before the court in support of women's rights that the justice embraces."

She has done a lot more than going duck hunting. She has actively sided with an organization that frequently has issues before the court. Just as I believe Scalia should recuse himself over the matter with Cheney, I believe Ginsberg should recuse herself with those cases involving NOW. I believe they should both be held to the same high standard, as should all judges, members of Congress, and members of the Executive Branch.