Here is a current list of "must have" active ping sites. Just go into your blog admin panel, >>Settings >>Writing >> scroll to bottom where it says Update Services and do a select all of whatever you have in there now and then delete them. Now copy/paste this list into it and save.

http://blogsearch.google.com/ping/RPC2
http://rpc.pingomatic.com/
http://rpc.weblogs.com/RPC2
http://services.newsgator.com/ngws/xmlrpcping.aspx
http://ping.feedburner.com
http://www.blogpeople.net/servlet/weblogUpdates
http://api.my.yahoo.co.jp/RPC2
http://xmlrpc.bloggernetz.de/RPC2
http://rpc.weblogs.com/RPC2
http://rpc.weblogs.com/RPC2
http://www.blogpeople.net/servlet/weblogUpdates
http://xping.pubsub.com/ping
http://ping.myblog.jp
http://ping.blo.gs/
http://ping.fc2.com/
http://ping.blogs.yandex.ru/RPC2
http://rpc.twingly.com