30 Largest Social Bookmarking Site part 1

According To Wikipedia Social bookmarking is:a method for Internet users to store, organize, search, and manage bookmarks of web pages on the Internet with the help of metadata.

In a social bookmarking system, users save links to web pages that they want to remember and/or share. These bookmarks are usually public, and can be saved privately, shared only with specified people or groups, shared only inside certain networks, or another combination of public and private domains. The allowed people can usually view these bookmarks chronologically, by category or tags, or via a search engine.
Many social bookmarking services provide web feeds for their lists of bookmarks, including lists organized by tags. This allows subscribers to become aware of new bookmarks as they are saved, shared, and tagged by other users.

1- Digg
Inbound Links :382,792,751
Compete Monthly Visitors :22,578,945
Quantcast Monthly Visitors :10,300,000
Alexa Ranking : 124
Page Rank : 8

2- Yahoo! Buzz
Inbound Links :900,571
Compete Monthly Visitors :128,556,575
Quantcast Monthly Visitors : 2,500,000
Alexa Ranking : 1
Page Rank : 6

3-Technorati.com
Inbound Links : 75,306,437
Compete Monthly Visitors : 3,231,709
Quantcast Monthly Visitors : 1,400,000
Alexa Ranking : 216
Page Rank : 8

4- del.icio.us
Inbound Links : 171,593,051
Compete Monthly Visitors : 1,699,128
Quantcast Monthly Visitors : 1,300,000
Alexa Ranking : 248
Page Rank : 8

5- Propeller.com
Inbound Links : 997,000
Compete Monthly Visitors : 1,454,912
Quantcast Monthly Visitors : 2,180,176
Alexa Ranking : 2,308
Page Rank : 7

6- StumbleUpon.com
Inbound Links : 19,050,177
Compete Monthly Visitors : 1,313,586
Quantcast Monthly Visitors : 695,239
Alexa Ranking : 300
Page Rank : 8

7- reddit.com
Inbound Links : 45,307,577
Compete Monthly Visitors : 2,587,503
Quantcast Monthly Visitors : 344,383
Alexa Ranking : 852
Page Rank : 7

8- mixx.com
Inbound Links : 6,175,082
Compete Monthly Visitors : 507,100
Quantcast Monthly Visitors : 475,000
Alexa Ranking : 1,880
Page Rank : 7

9- Fark.com
Inbound Links : 11,438,723
Compete Monthly Visitors : 306,597
Quantcast Monthly Visitors : 1,767,165
Alexa Ranking : 1,958
Page Rank : 7

10- MyBlogLog.com
Inbound Links :1,742,265
Compete Monthly Visitors : 1,972,847
Quantcast Monthly Visitors : 84,922
Alexa Ranking : 432
Page Rank : 7

Wait For part 2.
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