I did Hit Me Baby One More Time at the karaoke on Thursday and now the song's stuck in my head. It reminded me what a perfectly-put-together song it is. Leaving aside the vulnerable lyrics and the school-uniform video (part of what made it successful, obviously), it's musically really well-written and makes very crafty use of Britney Spears' voice.
The first vocal hook, for example, is "Oh baby baby". Hundreds of songs throughout history have used that line, but Britney Spears' singing makes it a proper hook. She pushes the vowels to the front of her mouth, but she also starts the "Oh" with what's technically known as "creaky voice". It's a sound that female pop singers sometimes use, and they seem to use it as some kind of sexual signifier (the vocal equivalent of come-to-bed eyes). Here it's not used quite so bluntly, and I think it's part of what makes the line distinctive. And it's one of many vocal hooks throughout the song.
The chorus is really interesting because you can actually barely hear Britney Spears' voice at all - most of the lines are driven by the backing chorus. It's clever because her own voice isn't really suited to pushing such a strong chorus along, so it's sufficient for her to be carried by the crowd and remind us she's still there when she chips in with an ornamental "And I".
The strange thing is that I happened to listen to the full album once and it's absolute rubbish, horrible sickly sentimental formulaic crap with horrible production. I don't know if it's just luck that they produced such a well-judged song as HMBOMT, or if they produced the single and then had to produce a full album's worth of filler in a couple of rushed days.