Well, I like her music, but, sadly, I've heard it too much on the radio, and I'm already tired of it (as it is often the case for me with music that is too often broadcasted on the radio).
When it comes to female songwriter, I prefer Susan Vega (the best scene performance I've seen so far. She was almost alone on stage with her guitar and a bassist. It was a incredible hour) and Ann Pierlé (a Belgian artist, I don't think that she's known outside of Belgium. Her first album is wild, I haven't listened to the second yet)
About my gnereal musical taste, I like Dave Matthews Band (too bad he's only touring in the US), The Divine Comedy, Radiohead, Ben Harper, Björk and many more.
But I can enjoy a haevy metal concert, or some (even 'experimental') electronic music (noise...). Some weeks ago I went at a friend's to listen to some concrete music (kind of sound landscapes, made out of samples of any noise you can imagine, water, clapping doors, mixed without any effect). I went there, curious, and actually loved it

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At parties I love to dance on what I would consider shit otherwise: the dance/soul/pop stuff you hear on MTV. In such cases, I even like the 'Wannabe' from the Spice Girls, or some crappy Britney tunes.