The Saudis were also opposing the Muslim Brotherhood in Egypt, more so than Obama, who is now failing to arm to the defenders of Christianity in Egypt.
However, Obama is managing to unite the world... (Israel, Argentina, Brazil, Iran, Turkey, Russia, Germany, even France) in a loss of respect for the American president. If they were friends of the US under Bush, that is a problem for Obama.
The MB is foiling the Saudis plans of imposing Wahabbism on the globe.
Saudi intel has a long relationship of helping and financing MB. Kamal Adham was cozy with them.
MB and Saudis are not opposing each other.