Come to know that Usability is one of the important factor in search engine ranking factors in recent times. A user should feel that this particular link should useful to me, when i click on this website link it should show something interesting stuff to me. I think like wise users should think right? So without getting a positive feedback from your audience you can't make sales right? Simply concentrating on back link building may not help us in this scenario. We need to concentrate on delivering the quality, rich and unique content to our audience, where they can trust it and rank it among others.