Thanks to Tom from Hull McGuire and Dan Hull’s What About Clients? BLawg for setting me right that more ping servers aren’t necessarily better. (Note: this ping server list is now maintained on Wikipedia)
http://api.feedster.com/ping
http://api.moreover.com/RPC2
http://api.my.yahoo.com/RPC2
http://blog.goo.ne.jp/XMLRPC
http://bulkfeeds.net/rpc
http://coreblog.org/ping
http://effbot.org/rpc/ping.cgi
http://ping.bitacoras.com
http://ping.blo.gs
http://ping.cocolog-nifty.com/xmlrpc
http://ping.feedburner.com
http://ping.syndic8.com/xmlrpc.php
http://rpc.pingomatic.com
http://rpc.technorati.com/rpc/ping
http://rpc.weblogs.com/RPC2
http://topicexchange.com/RPC2
http://www.a2b.cc/setloc/bp.a2b
http://www.blogdigger.com/RPC2
http://www.blogpeople.net/servlet/weblogUpdates
http://xping.pubsub.com/ping
(Note: this ping server list is now maintained on Wikipedia)









