How dangerous is smoking really? Is it as dangerous as the media makes it out to be, and is it more dangerous than other habits like drinking?

I often wondered this, as I'm constantly surrounded by smokers. I go to an art school, so basically everyone smokes. I'm just wondering why I've always been taught that smoking == death when I can clearly see people that have smoked all their lives and are fine. Also, if smoking your whole life is bad than what harm is a couple of years?

Most people I know claim that they know smoking is bad, and that they plan on quitting in a few years. Can serious harm be done to them by this point? While I know a lot of smokers I also know a lot of seriously rabid anti-smokers, who will just absolutely hassle someone for smoking because of the harm it does.