Bob Graham wrote a book about the findings from the 911 congressional inquiry. There's an interview with him here:
http://www.motherjones.com/news/qa/2004/11/11_401.html
It seems he concurs with the general, ‘inter-agency lack of co-ordination, cold war mentality and missed opportunities with hindsight’ consensus.
There are a few quotes however that pertain to his Saudi involvement claims:
‘MJ.com: How cooperative were President Bush and his administration with your inquiry?
BG: They started out with a lot of representations of how helpful they would be, in the same way that they did to the citizens’ 9/11 Commission that followed us. But when you actually started to dig close to sensitive information -- the most sensitive being the role of the Saudis -- they began to erect barriers.
MJ.com: Looking at the 9/11 Commission report that was completed after your inquiry, how did the findings of the two compare?
BG: In the main, it was very consistent. The basic intelligence failures that we found, and the recommendations to correct those failures, were largely adopted in the 9/11 report…
In the matter of findings, the biggest disagreement we had with the 9/11 Commission was on the role of Saudi Arabia. We found that there was compelling evidence that the Saudis played an active role in assisting two of the terrorists in Southern California, including being the means of substantial funding for those two terrorists. And this question of whether their support was limited to those two, or may have extended to others of the 17 terrorists, is still an unsolved mystery because the FBI did such an inept job of conducting that investigation. Whether we got it right or the 9/11’s softer evaluation of the role of the Saudis was right, we won’t know until after the administration makes available more information to the American people.’
Someone who has read the book told me that most of those 28 redacted pages have to do with the testimony of FBI agent Steve Butler. Butler was the handler of an informant that two alleged hijackers lived with. He was tracking money coming from the Saudi Government.