Top 10 Popular Sites:

1)  del.icio.us - [PR 8]
2)  Digg - [PR 7]
3)  Listible
4)  Furl - [PR 8]
5)  Yahoo My Web 2.0 Beta - [PR 7]
6)  Flickr - [PR 8]
7)  Slashdot - [PR 9]
8)  Youtube - [PR 6]
9)  Simpy - [PR 6]
10) Technorati - [PR 8]

1. 30daytags - General [PR5]
2. 34Things - To do List, Activity Lists [PR 8]
3. Aboogy
4. AllMyFavorites - [PR 4]
5. Article Tag - Social bookmarking service. [PR4]
6. aworldofhelp - [PR4]
7. Backflip - General [PR 6]
8. beanrocket - general [PR 6]
9. Bookkit - [PR4]
10. Bookmark Manager - [PR5]
11. BookmarkSync -[PR5]
12. BibSonomy - [PR1]
13. blabb.com
14. Blauer Bote Bookmarks / link - Bookmark manager for German & English [PR 5]
15. BlinkBits - [PR 4]
16. BlinkList - [PR6]
17. BlogHop - [PR7]
18. BlogLot - [PR 2]
19. BlogMarks.net - [PR 6]
20. BlogMemes.net - [Network also has French, Spanish and Portuguese version - BlogMemes.info] [PR5]
21. BlogLines.com - [PR 8]
22. BlogPulse - [PR7]
23. Blue.us - [PR4]
24. BookmarkTracker - [PR 5]
25. browsr - [PR5]
26. BuddyMarks.com - [PR6]
27. butterfly - [PR 4]
28. Chipmark.com - [PR 5]
29. clipclip - [PR4]
30. clipfire - [PR 6]
31. Clipmarks - [PR4]
32. commontimes - [PR6]
33. Connectedy - Converts browser bookmarks into social categories. [PR5]
34. Connotea - Social bookmarking for the scientific community. [PR7]
35. Complore (Research Collaboration Tool for Researchers)
36. del.icio.us - [PR 8]
37. de.lirio.us - [PR 6]
38. Digg - Technology site combining social bookmarking, blogging, RSS, and non-hierarchical editorial control. [PR7]
39. diigo - [PR6]
40. dinnerbuzz - for guide to restaurants, bars, and coffee shops anywhere in the world. [PR5]
41. Dog Ear - [PR3]
42. Dohat.com [P33]
43. Dutch Social Bookmarking site - This is the (currently only) Social Bookmarking site for the Netherlands. [PR3]
44. Fark - [PR8]
45. Favoor (Available in English and German) [PR3]
46. FeedMeLinks [PR4 /PR3]
47. Feedmarker - RSS and ATOM aggregator & bookmarks manager. [PR5]
48. Filangy [PR5]
49. Flikr - social bookmarks for photos [PR8]
50. Furl - this is similar to Similar to del.icio.us [PR8]
51. GetBoo - [PR1]
52. Gibeo - [PR6]
53. GiveALink - bookmarks for academic research [PR4]
54. GoKoDo MyBookmarks [PR4 - MAIN SITE]
55. GoobToob - Video clips, vote your favorite videos to the top, and submit new video clips.
56. Google Notebook
57. H2O Playlist - [PR6]
58. Hotlist Anywhere - [PR5]
59. Hot Links - [PR6]
60. Hyperlinkomatic - [PR5]
61. i89.us - [PR 3]
62. IceRocket - [PR7]
63. IndiaGram (Also has a voting system like Digg.com) [PR4]
64. Indiamarks (Bookmarking site dedicated to Indian community) [PR2]
65. Jots [PR6]
66. Kaboodle - [PR6]
67. Kinja - Blog bookmarking & aggregation service [PR 7]
68. leze.de and - German Internet Bookmarking Service [PR3]
69. Lilisto -[PR3]
70. linkaGoGo - [PR7]
71. linkfilter - [PR6]
72. linkroll - - [PR6]
73. LibraryThing - for books - [PR7]
74. Linux Bookmarks (LQ) - Bookmark, tag, annotate and share links to Open Source and Linux related sites - - [PR7]
75. ListMixer - [PR6]
76. Listible - [PR2]
77. Lookmarks (beta) - search & share bookmarks - [PR5]
78. Ma.gnolia - [PR5]
79. Maple - [PR6]
80. Mecanbe - - [PR 6]
81. memestreams - [PR 5]
82. Millions Of Games - casual games, tagged, rated and bookmarked by hundreds of users daily - [PR 5]
83. MotorKen - [PR 5]
84. MyProgs - Social bookmarking for the programs that you personally use, etc. - [PR 6]
85. Netvouz - [PR 6]
86. Network Menus - - [PR 4]
87. Newsvine - [PR 7]
88. NowPublic - [PR 6]
89. O Y A X - bookmarking service with groups - [PR 4]
90. PeerMark - [PR 4]
91. popurls.com
92. RawSugar - [PR 6]
93. Reader² - [PR 6]
94. Reddit - [PR 7]
95. Rojo - [PR 7]
96. Rollyo - [PR 6]
97. Rrove.com - social bookmark service for locations. - [PR 5]
98. Save Your Links - [PR 5]
99. Scuttle.org - [PR 6]
100. Scuttle - Download the script and start a bookmarking service. Web-based social bookmarking system. Allows multiple users to store, share and tag their favourite links online.
101. Segnalo - Italian Social Bookmarking - [PR 5]
102. Shadows - [PR 7]
103. Shoppersbase (Bookmarking website for online shoppers)
104. Shoutwire - [PR 5]
105. Simpy - offers Social bookmarking with tagging & full-text searching. - [PR 6]
106. SiteJot - [PR 5]
107. sitetagger - [PR 2]
108. Slashdot - [PR 9]
109. Smarking - [PR 5]
110. Spurl - stores copies of the pages saved. - [PR 6]
111. Squidoo - General topics [PR 5]
112. Start Aid - [PR 5]
113. Start - General by Microsoft [PR 7]
114. StumbleUpon
115. Social Bookmarking (Provides users with a personal social bookmarking sub-domain)
116. Sync2It's BookmarkSync - [PR 5]
117. Tab Marks - [PR 5]
118. taghop - [PR 4]
119. Tagsy - [PR 3]
120. TagTooga.com - [PR 5- main site]
121. TailRank - [PR 6]
122. Textnotes.de - [PR 4]
123. Technorati - [PR 8]
124. Tutorialism - Bookmarking website for tutorials
125. uLinkx - Social Video/Music Bookmarking
126. unalog - open source book marking software - [PR 5]
127. URLBlaze - url sharing tool. - [PR 3]
128. URLex - bookmarking & RSS feeds - [PR 4]
129. Wazima - [PR 5]
130. Web Feeds - [PR 5]
131. Wink - General social bookmarking + Search engine [PR 6]
132. Wiklink - Tool for use to synchronize bookmarks with your browser.
133. Wists - Shopping links, Visual bookmarks, wishlists and also photoblogs. [PR7]
134. World Wide Wisdom - [PR 5]
135. wURLdBook - [PR 5]
136. Yahoo! My Web - General bookmarking + sepcialty feeds + Available in many languages [PR 7]
137. Yoono - [PR 6]
138. Youtube - [PR 6]
139. Yummy! Social PDF Library - Bookmark and find PDFs and print them too! - [PR 5]
140. Zaadz - [PR 6]
141. Zurpy - [PR 5]