Taylor Swift has made the best CD of her young career with her fourth CD. The biggest difference is that Swift's singing, spotty on previous releases and live performances, is far far superior here.
Swift wrote all 14 songs here, which like her other albums tend to deal with relationships that have gone south. Swift's songwriting always has been one of her strengths, and that continues to be the case here - both lyrically and musically. Put simply, Swift knows a lot about penning catchy songs (Sparks Fly, Back to December, the title track and especially the fast, vibrant The Story of Us where her vocals are top notch)
She also co-produced the disc with Nathan Chapman, who previously turned the dials. The pair seem to have a good sense of matching the music to Swift's voice, which never sounds forced or stretched to the limit as it previously has.
Swift would never be mistaken for an out-and-out country singer (She's squarely a country pop singer), although several songs do maintain a country bent, particularly Mean with fiddle and banjo. The country quotient is just about besides the point at this juncture since Swift has gone far beyond country as an artist in terms of popularity and sales.
Swift's star has steadily increased from a commercial stand point, which has zero to do with the quality of her music. Questions arose as to whether she would be able to take her young fans with her as she aged. For her sake and to her credit, Swift also has grown as a musician.