I did some research to beef up my ping list. I tested some of the recommended lists (of which many do not work) and came up with my latest list – also tested for any duplicates.
http://1470.net/api/ping
http://api.feedster.com/ping
http://api.moreover.com/ping
http://api.moreover.com/RPC2
http://api.my.yahoo.co.jp/RPC2
http://audiorpc.weblogs.com/RPC2
http://bblog.com/ping.php
http://bitacoras.net/ping
http://blog.goo.ne.jp
http://blog.goo.ne.jp/XMLRPC
http://blog.youdao.com/ping/RPC2
http://blogbot.dk
http://blogbot.dk/io/xml-rpc.php
http://blogdigger.com/RPC2
http://blogmatcher.com
http://blogmatcher.com/u.php
http://blogpeople.net/ping
http://blogpeople.net/servlet/weblogUpdates
http://blogsearch.google.ae/ping/RPC2
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