Mega Champ

Here is list of sites you can update about your content as you post or in wordpress official words :
“When you publish a new post, WordPress automatically notifies the following site update services. ”

http://api.feedster.com/ping
http://api.moreover.com/RPC2
http://api.moreover.com/ping
http://api.my.yahoo.com/RPC2
http://api.my.yahoo.com/rss/ping
http://www.blogdigger.com/RPC2
http://www.blogshares.com/rpc.php
http://www.blogsnow.com/ping
http://www.blogstreet.com/xrbin/xmlrpc.cgi
http://bulkfeeds.net/rpc
http://www.newsisfree.com/xmlrpctest.php
http://ping.blo.gs/
http://ping.feedburner.com
http://ping.syndic8.com/xmlrpc.php
http://ping.weblogalot.com/rpc.php
http://rpc.blogrolling.com/pinger/
http://rpc.technorati.com/rpc/ping
http://rpc.weblogs.com/RPC2
http://www.azfeeds.com
http://www.blogsearchengine.com
http://www.blogtopsites.com
http://www.feedbase.net
http://www.feedsubmitter.com
http://www.fybersearch.com
http://www.plazoo.com
http://www.readablog.com
http://www.rssfeeds.com
http://www.rssmad.com
http://www.rss-spider.com
http://blo.gs/ping.php
http://www.pingerati.net
http://feedshark.brainbliss.com
http://www.pingmyblog.com
http://geourl.org/ping
http://ipings.com
http://www.icerocket.com
http://www.weblogalot.com/ping
http://rpc.pingomatic.com/
api.moreover.com/RPC2
api.my.yahoo.co.jp/RPC2
api.my.yahoo.com/RPC2
audiorpc.weblogs.com/RPC2
blog.goo.ne.jp/XMLRPC
blogpeople.net/ping
blogsearch.google.ae/ping/RPC2
blogsearch.google.at/ping/RPC2
blogsearch.google.be/ping/RPC2
blogsearch.google.bg/ping/RPC2
blogsearch.google.ca/ping/RPC2
blogsearch.google.ch/ping/RPC2
blogsearch.google.cl/ping/RPC2
blogsearch.google.co.cr/ping/RPC2
blogsearch.google.co.hu/ping/RPC2
blogsearch.google.co.id/ping/RPC2
blogsearch.google.co.il/ping/RPC2
blogsearch.google.co.in/ping/RPC2
blogsearch.google.co.it/ping/RPC2
blogsearch.google.co.jp/ping/RPC2
blogsearch.google.co.ma/ping/RPC2
blogsearch.google.co.nz/ping/RPC2
blogsearch.google.co.th/ping/RPC2
blogsearch.google.co.uk/ping/RPC2
blogsearch.google.co.ve/ping/RPC2
blogsearch.google.co.za/ping/RPC2
blogsearch.google.com.ar/ping/RPC2
blogsearch.google.com.au/ping/RPC2
blogsearch.google.com.br/ping/RPC2
blogsearch.google.com.co/ping/RPC2
blogsearch.google.com.do/ping/RPC2
blogsearch.google.com.mx/ping/RPC2
blogsearch.google.com.my/ping/RPC2
blogsearch.google.com.pe/ping/RPC2
blogsearch.google.com.sa/ping/RPC2
blogsearch.google.com.sg/ping/RPC2
blogsearch.google.com.tr/ping/RPC2
blogsearch.google.com.tw/ping/RPC2
blogsearch.google.com.ua/ping/RPC2
blogsearch.google.com.uy/ping/RPC2
blogsearch.google.com.vn/ping/RPC2
blogsearch.google.com/ping/RPC2
blogsearch.google.de/ping/RPC2
blogsearch.google.es/ping/RPC2
blogsearch.google.fi/ping/RPC2
blogsearch.google.fr/ping/RPC2
blogsearch.google.gr/ping/RPC2
blogsearch.google.hr/ping/RPC2
blogsearch.google.ie/ping/RPC2
blogsearch.google.in/ping/RPC2
blogsearch.google.it/ping/RPC2
blogsearch.google.jp/ping/RPC2
blogsearch.google.lt/ping/RPC2
blogsearch.google.nl/ping/RPC2
blogsearch.google.pl/ping/RPC2
blogsearch.google.pt/ping/RPC2
blogsearch.google.ro/ping/RPC2
blogsearch.google.ru/ping/RPC2
blogsearch.google.se/ping/RPC2
blogsearch.google.sk/ping/RPC2
blogsearch.google.tw/ping/RPC2
blogsearch.google.us/ping/RPC2
feedsky.com/api/RPC2
hamo-search.com/ping.php
holycowdude.com/rpc/ping/
newsblog.jungleboots.org/ping.php
ping.blogoon.net/
ping.blogs.yandex.ru/RPC2
ping.fc2.com/
ping.feedburner.com/
ping.kutsulog.net/
ping.myblog.jp/
ping.namaan.net/rpc
ping.snap.com/ping/RPC2
ping.syndic8.com/xmlrpc.php
ping.weblogalot.com/rpc.php
ping.wordblog.de/
r.hatena.ne.jp/rpc
rpc.bloggerei.de/ping/
rpc.blogrolling.com/pinger/
rpc.icerocket.com:10080/
rpc.pingomatic.com
rpc.reader.livedoor.com/ping
rpc.technorati.com/rpc/ping
rpc.technorati.jp/rpc/ping
rpc.twingly.com/
rpc.weblogs.com/RPC2
wasalive.com/ping/
www.blogpeople.net/servlet/weblogUpdates
xmlrpc.blogg.de
xping.pubsub.com/ping/
zhuaxia.com/rpc/server.php