I'm 17 and going to my final year of high school in January. I'm having some trouble making up my mind about what to do after high school and would appreciate some help with this.

I've skimmed a few books on career choice but they all just spout platitudes. I don't think I should do "What Interests Me" because I think I'd become bored of almost anything after a few weeks. I don't think I should do what I'm "talented" at because I doubt talents are specific enough to narrow down career-space enough. (Yes, a person might have high g and thus be good at computer programming, but that same high g would aid them as much with lots of other careers - why choose programming specifically?) Even if talents were specific enough, I don't think my self-assessments of what my talents are are even nearly accurate enough to base the next 50+ years of my life on them.

It's pretty obvious that most people have no idea what they're doing when they choose a career. So what should I base a career choice on?