Facebook, Linkedin, Google+ and many other social networks that can increase exposure of your brand are now attracting more and more people's attention. At first, I think it is very creative to build connections in the social networks. You can make friends with them and do business with them. You can share your common interest and sometimes you sell just what they want to buy. But now, i find that people tend to selfregarding. And sometimes it is just uncomfortable to find us be flooded with Ads.
Which is why the click through ratio on ads is less than 0.02%. Means only 2 out of ten thousand people actually click on the ad - i guess its enough for them to pay the price of ads bombardment But keep in mind there's no free lunch - free service mean paying in advertising. But on other hand; the advertisers turn to be more gruesome cause with that little of a CTR, they have no other option to keep advertising more and more ;-)
of course it is a good way to promote business.using these site can help the customers to find our business faster and easier.