How safe?

A lot of people prefer FB to MySpace because they say it's safer. But how safe is it, really? I mean, with every application you add, you give someone you don't even know access to all your information. There's no actual full-proof way to determine what people can actually see on your profile, and third parties are far from trustworthy.
As much as I hate to admit it, I frequently find friend requests from people who are most certainly peadophiles and child molesters, not to mention all the other freaks. However, I admit that the MySpace community is much more layed back when it comes to that sort of thing; with all sorts of pornographic images available for anyone who visits a profile, yet it still seems naive to think that FB is all that safe.
What I also don't understand is how people, especially girls, can post pictures of themselves in places like the beach and whatnot. Any pervert can download them off the internet and do God knows what with them.
That being said, I'm not deactivating my facebook any time soon; not until I find a valid reason to do so.