While I'll concede there were some obvious omissions of certain artists and stories as well as a generally glossy, patriotic view of American history (as Burns does in most of his work) I still found it very entertaining and informative. I learned some things about songs and singers I love, rediscovered some old artists that I haven't heard in years and got interested in some others that I never paid attention to. Isn't that what you expect from a music documentary?
All in all this series is classic Ken Burns. If you like his style and have ever enjoyed a country song, you'll probably love it. If you're not a fan of Burns or country music, there probably isn't anything here that's going to change your mind.