re: careful what you wish for
This activity, as popular as it seems, by visiting this and similar websites, is still no where near mainstream. Most people are still monogamous by nature, even if they do cheat occasionally on their regular partners. Still, the interest in sexually sharing partners is growing with couples, and the female's new "freedom movement" seems to be spearheading the growing interest. Men like to still think that they are in control of a relationship, but that's just not so any more, as more women become primary bread winners, and make comparable income to men. So, once his woman takes his hint to try a new partner, he may find himself no longer in control of what she does. Many of us guys do have fragile egos, and that emotional wheel of excitement, lust, envy, jealous, etc that we get when seeing our woman pounded by a more powerful man can suddenly become overwhelming and damaging to the relationship. Which is why so many ladies hesitate to act on their man's suggestions. Women realize, as being the more emotional gender, that sharing a partner is not a good idea, which is why women don't like sharing their men with other women.
So, yes, enjoy this kind of activity, but move cautiously, being aware of your spouse's responses to it as you progress, and by all means set parameters and lines of agreements that you both agree not to cross.