I have a very hard time resolving how this type of attack could fall under the umbrella of Anonymous. Saudis specifically attacking Israel implies a nationalistic attitude, given their history. They also affiliate their hacker group with Wahabbism, which is a strict branch of Islam that most would brand as fundamentalist (and sometimes extreme). I can't really see the ideals of Anonymous coexisting with nationalism a…
It's inspired by the Anonymous style: find someone you dislike, attack their computers somehow (e.g. private information theft, DDoS, web site defacing), and brag about it online. The ideals are very different, but the method is pretty similar.
After all the petty bullshit, Saudis like to party too. The problem is their government and society is repressive as hell, and they're so scared to confront it, they have to go into this whole make-believe world where they act as heroes by attacking Israeli servers. It's pretty funny. I'm sure Israelis will recover. The Saudis on the other hand still live in a medieval hellhole where women can't drive a car... and this really doesn't do much to change anything. Their time and energy would be better spent trying to bring civilization to their own wasteland.
[Edit] I should add, the fact that if you did this in your own country, you'd probably have your hands cut off, is a powerful motivation to go after somebody with more liberal values.