It would be tempting to compare this documentary to An Inconvenient Truth, but the comparison would ultimately fall short. When I walked away from An Inconvenient Truth, I felt as though I could make a difference in a policy and attitude with worldwide consequences. When I left the theater after Inside Job, all I really felt was despair. This would not seem a very positive review, but my despair came from a deeper understanding of the financial crisis of the last couple of years (and the film argues, of the last three decades). I know what happened but the documentary doesn't offer any actions I can take with this newfound knowledge, and instead makes the pretty clear point that any individual action I might take would not matter very much. In fact, as Mrs. Speculator pointed out, it turns out that by dutifully paying our mortgage, we've been helping to keep afloat the Ponzi scheme that Inside Job describes.
Inside Job does a good job of describing the roots of the financial meltdown of 2008, so much so that it points out that there have been a series of increasingly worse financial crises for decades now. Inside Job also makes it painfully clear that what has happened is not based on partisan activity—conservative and liberal presidents alike have followed the path that has led to the economic situation we find ourselves in: the derivatives market, a sort of lottery once removed from explicit market movements, has become the profit leader for the financial services industry and every attempt to regulate derivatives has met with adamant opposition. And essentially the derivatives market is based on high-risk investment, which the movie compares to gambling, except that our government has deregulated to the point that the companies that are gambling are "too big to fail." As a result, if the gamble comes through, those companies and their employees make ungodly profits, and if the gamble fails, those same companies are propped up by the government because their failure could lead to crises that would make our current issues appear petty.
Inside Job stops just short of calling anyone of the players criminal, but it makes no bones about the immorality of what they do. Some of the people who are interviewed do call for investigation which, given the implications and innuendo that the documentary does provide, seems a fine starting point for resolving the issues the movie raises. The faceless interviewer also does not appear hesitant to outright tell his subjects they are heavily shading the truth. In fact, perhaps through no fault of its own, towards the end of the movie, it comes to feel like a chorus of deception as very smart people say things that are demonstrably false.
The underlying question that Inside Job only rarely asks is one of morality. It becomes clear over the course of the movie that the motive of those responsible for what happened may not have been at all evil. The narration makes it clear that it thinks the participants should have been more concerned about how their actions would affect the common man, and the interviewees don't seem to feel that way at all. This disconnect mirrors recent House testimony regarding executive pay and bonuses, where witness after witness testified that they felt the huge bonuses often luridly described in the media were well-deserved. And from the point of view of those witnesses, some of whom appear in the documentary, it does make a libertarian sort of sense: they were hired to maximize the profits of the company that employed them and issues that do not explicitly affect that profit line are insignificant. From this different perspective, those executives actually do deserve their bonuses when they are bailed out, solely for preserving the profit margin and seeing governmental bailout as another source of income.
What Inside Job doesn't do so well is explain why that attitude is unhealthy, beyond the fact that is doesn't really seem fair and that it is creating a larger gap between the classes. Said another way, the movie is full of moral dudgeon, which is a perfectly appropriate response, but it never goes on to talk about what's going to happen if the trends continue. Even when the movie is the most explicitly moralistic, when it describes the bizarre relationship between economic professors who write glowing papers on failed economic policies and the companies and countries who pay them to do so (thereby enhancing the appearance that these people are both smarter than everyone else and also doing the Right Thing even though that Thing fails), it doesn't really offer any sort of recourse than to cinematically pout. To be sure, the larger trend that Inside Job describes does indicate that worse crises are coming, because we can't seem to regulate the greed that drives high-level capitalism.
The result is a mixed bag. If you are uncertain or plain just don't understand how we got to where we are, or if you have no idea what a credit default swap is, Inside Job does a great job of explaining the history and the decisions that led us here. What it fails to do is go beyond the moral dudgeon I mention and tell the viewer what they can do about it, other than get really mad, which is what I felt when I left the theater. Perhaps that really isn't within the scope of what a documentary is supposed to do, or the filmmakers felt that adding that kind of information would become tedious or boring—it's far more interesting to talk about how others have mistreated us than to show how to put a halt to that mistreatment. Of course, perhaps the answer is that individuals really can't do anything, which I suppose would be a far worse ending for a movie than just feeling discouraged.