In a brief biography of al-Rubaysh that appeared on one of the forums it claims that he is a graduate of Imam Muhammad bin Saud University in Riyadh and that he, no surprise, spent time in Afghanistan before being arrested and sent to Guantanamo.
The tape is basically an explanation of why AQAP targeted Muhammad bin Nayif. I don't think there is too much new here for those who follow Yemen and Saudi closely - it has been clear for a long time that Muhammad is AQAP's most dangerous enemy, at least from the standpoint of doing the most to destroy the organization. Still, a couple things stood out to me - allegations about Saudi using the wives of al-Qaeda members against them and the idea of grudges from Guantanamo. Both of these fit into what I've seen and heard before, but I want to listen to the tape a few more times before expanding.