At Get Religion, "Orthodox or extremist?", a reflection on the use of the term "orthodox" in media religion stories. It quotes from a NY Times article which includes the following paragraph:
But whether the matter under debate is central or peripheral, making a claim to the [orthodoxy] label obviously does not settle the question of what is true doctrine, or true patriotism. And the news media should be as careful not to echo the partisan language of adversaries in the religious case as in the political arena.
My impression is that the mainstream media is inclined to use the term "orthodox" with a negative connotation, trying to label conservative believers as too conservative or even extremist. By contrast, the term "liberal" is used to describe believers who, whether orthodox or not by the lights of the denomination under consideration, are considered acceptable or preferable to the mainstream media. Maybe some of you see the typical media usage of these terms (often imported from political discussion directly into commentary on religious differences, as noted in the article) differently.
Use of the term "orthodoxy" in LDS discussion is complicated by the fact that there is no LDS catechism that defines doctrinal orthodoxy. From time to time, one runs into speculation that the equivalent term for measuring conformity to LDS norms is "orthopraxy" or right practice rather than right belief. This seems like the right approach to me, although obviously there is still a doctrinal component to consider.