As hooked as I am, I don't put personal details on there. I'm always a little surprised at what people post for 600 of their closest friends to see!
As for not having a Facebook making you less trustworthy- I completely disagree. 99% of what I see on Facebook is either complete fabrication or grossly exaggerated. I see women with 18 albums full of cropped headshots. I see mothers posed with their scantily clad 15 year old daughter commenting on how beautiful she is. If you believe everything you see on Facebook, you'd have to believe that women ALWAYS have their hair done and their make up on. Every man in America has a piping hot five course home made meal waiting when he gets home. Kids never tell you you're the meanest mom ever. And we all secretly hate our best friend.
I wouldn't trust anyone who thinks you're sketchy for not having a Facebook!