What's a "Fiduciary"?

Even though I disagree with most of Forbes' editorials, Neil Weinberg had a mostly excellent article in the August 9th issue. He begins,
"Everybody hates Wall Street and it's easy to see why. While one in six workers can't find a job, investment banks are hiring thousands. Goldman Sachs Chief Lloyd Blankfein recently bought an apartment on New York City's Central Park West for $26 million-in cash. How are you doing with your mortgage payments?"
He goes on to say that, after the industry wide $700 billion taxpayer bailout, New York City's financial sector awarded itself $20 billion in bonuses, an average of $124,000 for each banker, analyst & secretary. BONUSES, not wages. Bonuses. He adds, "Say, how is your 401(k) holding up?"
But here is where I really agree with Mr. Weinberg: he says it's our own fault for not standing up and insisting on real reform, for not holding our Congressional representatives accountable to us.
For example, initial versions of the recently passed financial reform bill required "fiduciary" standards for all financial advisers, including stockbrokers. "Fiduciary" means the adviser must put the client's interests above his own. That provision didn't survive, after heavy lobbying from the industry. Brokers can continue offering expensive crap that makes them the most money as long as we're dumb enough to keep buying it.
This, too, Weinberg places squarely in our own laps: Why would we continue dealing with people we know don't have our best interests at heart? Why not deal only with true fiduciaries, such as RIAs (registered investment advisers, like me)?