Here is additional insight on AIG from the NYTimes:
http://www.nytimes.com/2009/07/31/business/31aig.html?pagewanted=1&hp
"But state regulatory filings offer a different picture. They show that A.I.G.’s individual insurance companies have been doing an unusual volume of business with each other for many years — investing in each other’s stocks; borrowing from each other’s investment portfolios; and guaranteeing each other’s insurance policies, even when they have lacked the means to make good. Insurance examiners working for the states have occasionally flagged these activities, to little effect.
More ominously, many of A.I.G.’s insurance companies have reduced their own exposure by sending their risks to other companies, often under the same A.I.G. umbrella."
“An organization like this one relies on constant, ever-growing premium volume, so it can cover and pay for the deficits,” said W. O. Myrick, a retired chief insurance examiner for Louisiana.
If A.I.G.’s incoming premiums shrink, he warned, “the whole thing’s going to collapse in on itself.”