Great country comes from this style of songwriting that completely emphasizes lyricism in favor of almost any musicianship, and I think, for the most part, that's the difference between that and folk (that and perhaps the fact that folk either concerns itself with these fantastic ideals/stories/bourgeois ideals or the "plight" of America - whereas country is extremely introspective and based entirely around telling stories about the singer's life). There's a certain sense of loss, of living day to day instead of planning, wandering and wanderlust to country, and this normally accompanies and incredibly brutal honesty and personality.
Suffice to say, I love country - some of America's greatest songwriters.