Superjast et al,
Thanks for the thoughtful reply. I'll definitely try more face-to-face meet-ups. My wife is also willing to help by talking to potential matches. I should realize that everyone is different and that many women will need many weeks (possibly months) of talk before meeting. My wife is not at all like that though, and it may have given me a false impression that if someone doesn't want to meet after a month or two that something is wrong. My wife likes to make the initial contact via the internet, but then move to meeting as soon as possible (usually after a few days of messaging and talking). One thing she does to help her peace of mind about safety is to get their full name prior to meeting, then checking them for a history of criminal activity (here in Arizona we have a free, publicly accessible website to search all court cases in the state). She also checks the state-wide sex offender registry.
PS: I've now read the "Nonmonogamy for Men" essay recommended by jkelly (linked in msg #11 of this thread). I'd like to second the recommendation; very well done and informative! I've got it saved to my hard drive for reference.