A new survey asked 9,400 Americans how interested they'd be in an OPEN RELATIONSHIP . . . which they say is, quote, "where you could date more than one person simultaneously." And 28% of Americans say they'd be interested, including about one in seven people who'd be VERY interested. 13% of people say they're not really interested . . . and only 52% have zero interest. In other words, it's basically a coin flip whether your partner is totally against it or not. Men are much more likely than women to say they're interested in an open relationship, 34% to 23%. And people under 34 are WAY more interested than older people. Almost half of people under 34 are interested . . . versus 13% of people over 55.