King Salman's crown prince was already known, as predecessor King Abdullah had unprecedentedly appointed a deputy crown prince a few years ago - another half-brother, Prince Muqrin. Salman has not only confirmed Muqrin - ten years his junior - as the new crown prince, but also filled the deputy crown prince role with his nephew (by one of his full brothers, former Crown Prince Nayef who died before he could assume the throne, thus paving the way in fact for Salman) Mohammad bin Nayef, the hardline Interior Minister. This would seem to assure the necessary smooth transition to the generation of Abdulaziz's grandsons, and while it might put Salman's own sons out of joint a little, it does interestingly keep the long-term succession in the hands of the so-called "Sudairi faction", the families of that group of seven brothers whose mother was Princess Hassa al-Sudairi. The new king's own son, Mohammad bin Salman has in turn become defence minister, replacing his father. Whether this does indeed narrow the future succession to the Sudairis remains to be seen, and there are rumours that that once tight faction is itself subject to some internecine struggling, but it is certainly clear that Crown Prince Muqrin will be the last of the immediate sons of King Abdulaziz to become king in succession to Salman. Muqrin's own position was controversial, as his mother was a Yemeni concubine rather than a pure Saudi wife, but perhaps a Yemeni connection is no bad thing at a time when the southern arab country is causing so many headaches for Saudi Arabia.
Why does this matter? Well, apart from the inherent fascination of an almost medieval tableaux of court politics that the kingdom provides, it remains one of the two key regional powers - along with its old enemy Iran - and is a key to American interests in the region. Its ability to manipulate world oil prices is being seen at the moment as it maintains oil production at the same rate but lower prices without causing undue economic stress to itself. It is a key ally against Isil, a counter-weight to Iran, and the stable home to two of Islam's holiest shrines. That Saudi Arabia is in Isil's sights is apparent from a recent attack by that group on Saudi border guards. Isil have already made it clear that they regard the Saudi control of Mecca and Medina as wholly wrong, and would love to wrest the cities away. This may seem like a pipe dream but Saudi Arabia takes its border security seriously enough to have initiated the erection of an impressive 600-mile wall along its northern border with Iraq, similar to the 1000-mile one it already has across its southern border with Yemen.
King Salman - by all accounts a shrewd and respected leader, who even established a private jail for misbehaving Saudi princes - will already be familiar with the problems of a Yemeni government that has just fallen (to allegedly Iranian backed guerrillas, the Houthi); a continuing high risk strategy on oil prices and production contrary to the rest of Opec's wishes; the threats from Isil; and the policy to see Bashar al-Assad removed from Syria. As he juggles these, he also needs to work out just how much reform - if any - the powerful Saudi religious establishment will take (and he appears not to be as personally committed as his older half-brother), as well as keep his increasingly fractious family in line. He may not have much time either. Whilst foreign visitors remark that he retains his sharpness in conversation, there are rumours of an onset of either dementia or Parkinson's. Another reason, perhaps, for the seventh Saudi king to have quickly put the putative numbers 8 and 9 in place so quickly.
Further - Joshua Keating on Slate.com examines Salman's difficult inbox; Newsweek on Saudi border concerns; and the Washington Post on the generatiom shift in Saudi royal circles.