I have no problem if their lifestyle doesn't interfere with me. They have certain rights, and so do I.
But the thought process was more along the lines of how it might affect me, with the types of people that are showing up in my neighborhood. One would think that jealousy would have to be a prevalent emotion among swingers. And jealousy is certainly something that can cause people to do irrational things, regardless of their mental stability. So think of it more as a general question of morality and people who are drawn to a particular "lifestyle" than "who's sleeping with whom." I know this thread really has nothing to do with homosexuality, but I just thought it was an interesting comparison to see where each situation ranks on the morality scale.