Well, first of all, KRM, that description was used in the context of describing an exchange between a political figure and the editorial page editor of that paper, so if that paper is known for its strong conservative views, as Guin now confirms for us, yes it forms a relevant part of the context of the story.
Second of all, the problem of referring to the “liberal New York Times” is not so much a problem of labeling but of mislabeling…i.e., a question of whether the term is accurate or not. It is hard to call a newspaper that has reporters such as Judith Martin writing exciting stories, which we now know to be essentially fiction, about WMDs in Iraq…that relied excessively (exclusively?) on the reports of a few defectors produced by Chalabi’s Iraqi National Congress. Their editorial page is left-of-center but not by much.
I would have no problem with a story that talked about an exchange between, say, Laura Bush and the editor of the alternative free weekly paper here in Rochester, Rochester City Paper, referring to that paper as liberal. (And, the same could probably be said of a lot of the alternative free weekly papers that exist in many cities.)