List of Top Social bookmarking Sites sites that major search engines give top priority.
http://www.digg.com/
http://www.technorati.com/
http://del.icio.us/
http://www.propeller.com/
http://www.stumbleupon.com/
http://www.reddit.com/
http://www.fark.com/
http://www.mybloglog.com/
http://www.slashdot.org/
http://www.kaboodle.com/
http://www.bloglines.com/
http://www.newsvine.com/
http://www.blinklist.com/
http://www.mytalk.at/
http://www.netvouz.com/
http://www.clipmarks.com/
http://www.furl.net/
http://www.mister-wong.de/
http://www.dzone.com/
http://www.ma.gnolia.com/
http://www.tailrank.com/
http://www.shoutwire.com/
http://www.simpy.com/
http://www.blogmarks.net/
http://faves.com/home
http://www.spurl.net/
http://www.spotplex.com/
http://www.linkswarm.com/
http://www.spotback.com/
http://www.plugim.com/
http://www.mybookmarks.com/