Until a few years ago, tracking the evolution of language was only possible for idle gentlemen: university scholars, amateur dilettantes (whence arose the Oxford English Dictionary), or pompous columnists (only one of whom has a weekly piece in the New York Times Magazine). It was carried on from an elite gentleman's club perspective and consisted of deploring decline and patronizing neologism.
But now we have the tools to do a vastly better job of paying attention to what *we* are saying. Huge quantities of "real" language as it is spoken and written can be collected easily and subjected to sophisticated tracking analysis. Gender, class, nationality: all can be revealed and studied as never before. The ethical and political bases of society as it is (not as it imagines itself to be) can be displayed and analyzed.
Why is this important? Because the way we talk about ourselves and others is the way we create ourselves and our society. The ethical and social revolutions of the last half century have been far reaching, but it is still possible for those who prefer nostalgia to justice to wish those revolutions away. The emergence of a serious journalism of language, supported by good science, would document the way in which all classes and social groups have changed and continue to change. It would tell us things about ourselves that we know in our hearts but have not had the self aware and the wisdom and the courage to say to ourselves aloud. I believe we would all be happier if we knew how far we have come, and I can think of no better way of measuring and showing it.