Because Justin Bieber is Justin Bieber -- a teen-singer heartthrob -- it's hard to take his music seriously. Everything about him screams Tiger Beat, from the endless screeching girls to his relationship with fellow teen sensation Selena Gomez to that hair (let's not forget about the promotional products, from his perfume lines and those Proactive commercials).

And then there's the song that has defined him most -- "Baby," perhaps the most saccharine, bubble-gum song recorded in quite some time.

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