The nytimes wrote an interesting article on this a while back titled "How We Value The Super-Rich." It suggests that Americans don't have a general resentment towards the wealthy, but rather a resentment toward rich people who aren't perceived as generated wealth.
A couple of quotes:
"The super-rich of high-tech, on the other hand, create tangible things that make our lives easier, and this we can respect. Steve Jobs gave us the ubiquitous iPod. Larry Page and Sergey Brin, the roller-blading Google guys, devised a better way to search the Internet. Jeff Bezos gave people a way to shop in their pajamas. Bill Gates makes the desktop software on the computers most people use every day."
"In contrast, the public seems to resent the big boys of Wall Street because they do not appear to have invented anything -- unless you count ingenious ways to make more money. Option derivatives are as inexplicable to the general public as particle physics. Richard Fuld of Lehman Brothers, Alan Schwartz of Bear Stearns and Robert Willumstad of AIG might have tremendous records of innovation. If they do, none of us were told."
I actually think that much of the supposed American resentment toward the "rich" is anger with wall street. I have a feeling that some wall street PR will attempt to use this ambiguity, attempting to equate anger toward bailed out banks with a general hostility toward capitalism, investing, rich people in other sectors of the economy such as high tech, etc....
I also think that it would be foolish for "the left" (am I allowed to say that?) to play right into this by acting too alarmed about wealthy people who clearly have created great wealth.