Discuss: Which social networking sites are the Best?

This thread is to discuss the opinion poll topic 'Which social networking sites are the Best?

I would like to know about the users where they spend most of their time on the above mentioned social networking sites. I know everyone is using all of them and it will also depend on the personal interest of every individual. So considering the above options lets discuss which one is the best.

For me it is the Facebook. Because I have spent a lot of time finding my friends on the other social networking sites whereas all my friends were already present and registered on Facebook. So I was the last to get my account there. I use the other social networking sites also but their use is very limited.

Apart from these social networking sites; I would like to specifically mention; Maharashtraspider.com should be the best site because it provides us so much to work on. Today after getting so many points on this Maharashtraspider channel; I feel lucky to be spending my time making money and getting points too. Also, many a times, I feel that I am wasting my time if I have not logged into my Maharashtraspider channel account.