ok, well. using jen and venus as an example. they've played a couple of times but they dont play each other very often so it cant really be called a rivalry however players like justine and kim who play each other all the time, well they have a rivalry.
Go the aussies! stosur!!!
and good luck russians: dementieva, safina, kirilenko, sharapova, kuznetsova, bovina, zvonareva, dushevina.
also good luck to: azarenka, lucic, sprem, vakulenko, vaidisova, safarova, ivanovic, groenefeld, mirza, krajicek, kvitkova, larcher de brito, lisicki.