"The United States will assist the Kingdom of Saudi Arabia to develop civilian nuclear energy for use in medicine, industry, and power generation and will help in development of both the human and infrastructure resources in accordance with evolving International Atomic Energy Agency guidance and standards."
The deal coincided with President Bush's recent visit to the magical Kingdom, however, he wasn't the first Western head of state to offer the Saudis nuclear energy assistance. French President Sarkozy did so last January (which is something of a habit for Sarkozy, who has also expressed his willingness to provide civilian nuclear assistance to Egypt and the United Arab Emirates). Apparently the Saudis have been looking for this kind of assistance for some time.
There will be much predictable scoffing about why the Saudis would have any use for nuclear energy in "medicine, industry, and power generation," but it's really not so odd given that Saudi Basic Industries Corporation (SABIC) has been making a major effort to market itself as an investment destination for petroleum spin-off industries. For example, last year SABIC entered into a joint venture with Dow Chemical to produce plastics and other 'downstream' petroleum products in Saudi Arabia, and also acquired the plastics division of GE. I can easily see why it makes sense to move the plastics industry to Saudi Arabia, since that will put manufacturing facilities next to almost unlimited amounts of the feedstock chemicals and power they need. I suppose the same reasoning could apply to many other industries.
Water desalination is another good reason to produce nuclear energy in the Kingdom. About 70% of Saudi Arabia's drinking water is produced in 30 or so desalination plants and those plants require about 21 percent of all the electricity now generated in the Kingdom, according to articles like this one and this one. The Saudis need to build even more such plants, and that's clearly an attractive scenario for nuclear power.
Could the Saudis also want to acquire nuclear weapons? Maybe; here's a research thesis that suggests why they might. But surely they could do that much more easily by funding under-the-table weapons efforts in Pakistan than by building the weapons themselves. Developing nuclear weapons is not so easy, even for a wealthy nation. The Israelis did it [read The Bomb in the Basement to see how and why] but only after many years of effort during which they first developed a world-class scientific establishment, obtained critical assistance from certain guilt-ridden officials in post-World War II France, and persuaded the United States to look the other way at times. The Saudis just might want to have a few nukes, but I don't think this new agreement will be a route to get them.