Here is what Wikkipedia had to say about takfeer:

Hassan al-Banna, the Egyptian founder of the Muslim Brotherhood, is said to have been influenced by the Wahhabis. The Muslim Brotherhood also claimed to be purifying and restoring original Islam. When the Muslim Brotherhood was banned in various Middle Eastern countries, Saudi Arabia gave refuge to Brotherhood exiles. This seems to have set the stage for a mingling of Brotherhood and Wahhabi thought under the aegis of the term Salafism. Rebels against the Saudi state found justification in the thought of Sayyed Qutb, a member of the Brotherhood who spent years in Egyptian jails. Some Wahhabis, or Salafis, rejected what they call Qutbism, as a deviation from true Salafism. Thus there is now a considerable spectrum of religious opinion within Saudi Wahhabism/Salafism, to a great extent divided on the question of whether the Saudi state is to be supported, endured patiently, or violently opposed. The modern day Salafis, deny that Hassan al-Banna or Sayid Qutb where followers of the Salaf, since they upheld the view that it is allowed to overthrow the Muslim leader, and to make “Takfeer” (the act of placing a Muslim out of the fold of Islam, making him a disbeliever) on him based on Major Sins.

From the Saudi royal family’s point of view, this reindoctrination preserves the Salafi view that they have the world’s only true religion, but it makes the royal family “off limits” as far as purging the land of the two holy mosques of corruption. “Graduates” must pledge fealty to the king. This is the same issue that got Osama bin Laden kicked out of KSA in the first place. So, why are so many Saudis still supporting Al Qaeda in Iraq?