I know that in the days after 9-11 scientist and researchers
did start to question why building 7 collapsed and after the offical report came out they came to the conclusion that on several major points questions were not answered in the report and that they had made different conclusions, but weren't allowed access to research material. Building 7 was never hit by a plane and yet it collapsed. There was no evidence for heavy fire or heavy structural damage to the building, and there were buildings closer to the two WTC towers that also had only minor damage (considering what happened quite near to them). Even if there had been evidence of major fire, according to these scientists, steel buildings do not collapse from fire, see what happened to the building in Madrid more than a year ago (don't remember the exact date), it burned out completely, yet remained standing because the temperature of normal fire does not reach the meltin point of steel.
So, I'm not a scientist but when I read articles about this, I don't necessarily take it as the absolute truth, but it does make me wonder, and makes me want to investigate it more, read more about it, and that's just what a lot of people have started doing, and I was actually expecting Oliver Stone to be doing that as well!
I am not fond of conspiracy theories, but I AM fond of the truth. On wikipedia there is a list of organisations and people who are doing independent research into 9-11, including the 9/11 Family Steering Committee, you can see the list here:
http://en.wikipedia.org/wiki/Researchers_questioning_the_official_account_of_9/11#9.2F11_Family_Steering_Committee