I love her music and I actually think she has pretty good taste in clothing. She's definitly aged gracefully with her style unlike many in the music business. She used to be ultra hip rock chick looking ready to party, now she's really matured into a woman without losing her cool factor.
I must say, she gets major props for looking tasteful in an industry that seems to get more and more trashy everyday (well, except for that yellow Cavalli number, she's got the body for it no doubt, I just don't like the dress)
Just a side note, both of the dresses she's wearing at the MET events are by Ralph Lauren.