Hahahahaha, I can't stop laughing!!
One YouTube guy just showed up at my house once, even though I had never given him my address. He had figured out where I live by looking up my parents' names on Facebook, and matching up the view from my door with a clip I had in one of my videos (which I have since deleted). That was pretty creepy and really made me think twice about mentioning anything on my YouTube channel regarding the exact city I live in, where I work, etc.
On the other hand, I've agreed to meet up with a couple people from YouTube, but always in safe situations. Meet during the day, at a very public place, that sort of thing. Two guys came to see me in a play I was in, which was pretty cool because I got to talk with them after the show but in a crowd of other audience members and with cast members nearby. One of them brought me something and had left it in his van and they asked me to go with them to get it, I said I wasn't comfortable with that so I waited in the theater while they went and got it. One of these guys is one of my closest friends now so I know he wouldn't have hurt me or anything but it's always best to be safe.