@Dresan I agree with you to a point about cartoons as the gateway drug (and would amplify it with TV and movies), but it won't work with somebody who isn't already "a reader."
I cut my teeth first on Star Trek, then my dad handed me Asimov (Foundation, of course), and I was hooked. But someone I haven't seen named yet is Orson Scott Card. And jeebus! I hate Card, but Ender's Game might be the best gateway to SF ever written. And I say this having just reread it for like the fifth time. And I am horrified - horrified, I tell's ya! - that it is now shelved in YA fiction at my library. And the cover art is now geared towards the young 'uns, too.
As for urban fantasy, I freaking hate it. Freaking. Hate. It. The whole reason I read SF and fantasy is to get to place that doesn't exist, that takes me out of the everyday. Why on earth would I want to read about faerie intruding on my home town. I read to get out of my home town, fer crissakes. Clive Barker's Abarat is the definition of this, in a way, starting in an awful hometown and completely removing the protagonist from it. She's a regular person who wants to, and does, escape.