A website with similar interface to SO or Quora would be very useful.
No, I wouldn't use it.
Have you seen the rubbish on relationships on Yahoo Answers?! Sheesh, there's some special kind of crazy people on there.
I'm sorry. I'm not understanding what your service would do. What would it do?
Check out http://leftos.com
http://www.reddit.com/r/seduction/