In my opinion, the dominant motivation behind the "Occupy Wall Street" movement is the high unemployment rate and the widening gap between the wealthiest one percent of Americans and the other 99% of Americans. Because such a disparity between these two groups exists, the protesters can claim to be speaking for this percentage of Americans. As someone who is under-employed and has a PhD, I can appreciate the frustration and anxiousness of many Americans searching desperately for a job.
Unfortunately, from what I have been able to ascertain, the "Occupy Wall Street" movement lacks focus and lacks a central spokesperson. Furthermore, they have engaged in some violent actions that have ended up hurting small business persons and innocent citizens.
Of course, what those engaged in the "Occupy Wall Street" movement may not realize is that it is the richest one percent of Americans putting their money to work that will bring us out of this economic funk. Alas, the reports I hear say that many major companies have massive reserves of cash that are sitting on the sidelines and are not being used to hire more workers to make more products. Interestingly enough, a high unemployment rate is actually good for Wall Street because paying fewer workers means that companies are not spending as much to produce their goods and therefore their profit margins move higher; and when profit margins move higher, stock prices typically advance.