Facebook
Social networking website, users can add friends and send them messages and update their personal profiles to notify friends about themselves.

Google Pagerank:

0

Alexa Rank:

2

Estimated Traffic:

2,147,483,647
Diigo
Two services in one - it is a research and collaborative research tool on the one hand, and a knowledge-sharing community and social content site on the other.

Google Pagerank:

0

Alexa Rank:

1585

Estimated Traffic:

632,058
Slashdot
When Slashdot links a site, often a lot of readers will hit the link to read the story or see the purty pictures. This can easily throw thousands of hits at the site in minutes.

Google Pagerank:

0

Alexa Rank:

1732

Estimated Traffic:

941,260
Newsvine
News media site that presents news, like what you would see on news sites like MSNBC or CNN, but in a much more attractive interface.

Google Pagerank:

0

Alexa Rank:

3970

Estimated Traffic:

1,800,870
Mixx
All of the content is user-generated, which means that we don’t have an editor who decides what you should find interesting.

Google Pagerank:

0

Alexa Rank:

446462

Estimated Traffic:

3,404
Delicious
Social bookmarking service that allows you to tag, save, manage and share Web pages all in one place.

Google Pagerank:

0

Alexa Rank:

428

Estimated Traffic:

1,382,153
Technorati
Blog search engine featuring real time blog posts and social media content from around the web. Visitors can browse for blogs by category, keyword or web presence.

Google Pagerank:

0

Alexa Rank:

1347

Estimated Traffic:

986,494
AolNews
Social news web site that is owned and operated by AOL. AOL is a leading global ad-supported Web company, with a comprehensive display advertising network in the U.S.

Google Pagerank:

0

Alexa Rank:

39216

Estimated Traffic:

614,919
Reddit
Source for what’s new and popular online. vote on links that you like or dislike and help decide what’s popular, or submit your own.

Google Pagerank:

0

Alexa Rank:

121

Estimated Traffic:

10,293,194
TweetMeme
Aggregates all the popular links on Twitter to determine which links are popular. Tweetmeme analyses links that people have “tweeted”, organising and categorising them.

Google Pagerank:

0

Alexa Rank:

1238

Estimated Traffic:

419,247
StumbleUpon
Helps you discover and share great websites. As you click Stumble!, we deliver high-quality pages matched to your personal preferences.

Google Pagerank:

0

Alexa Rank:

148

Estimated Traffic:

20,685,047
Google Buzz
Start conversations about the things you find interesting. It’s built right into Gmail, so you don’t have to peck out an entirely new set of friends from scratch.

Google Pagerank:

0

Alexa Rank:

1

Estimated Traffic:

2,147,483,647
Twitter
Twitter is considered as the best social networking and Bookmarking site due to its simplicity and applications!

Google Pagerank:

0

Alexa Rank:

8

Estimated Traffic:

204,151,551
Yahoo! Buzz
Yahoos attempt at bringing the Digg style website to the masses. Although not as popular as the aforementioned Digg it’s slightly easier to gain a high ranking site.

Google Pagerank:

0

Alexa Rank:

4

Estimated Traffic:

7,485
Digg
News site that allows anyone to submit to the system. Users then vote, or 'digg' up articles. Popular articles gain thousands of unique visits.

Google Pagerank:

0

Alexa Rank:

180

Estimated Traffic:

3,930,983