List of social bookmarking sites

As per the trends of social networking please review following sites are best social bookmaking sites ever. It will be use for sharing knowledge, update and news.

www.Facebook.com
www.Twitter.com
www.MySpace.com
www.Pinterest.com
www.LinkedIn.com
www.plus.google.com
www.Tagged.com
www.Ning.com
www.myLife.com
www.Badoo.com
www.Habbo.com
www.pinnme.com 
www.Habbo.com
www.Zorpia.com
www.Xing.com