interesting article on high frequency trading, page-2

Yes, Goldman Sachs has achieved the position of charging outsiders a fee for being able to trade on a stock exchange. Their computers have been installed on the trading floors, their software has been allowed to see your orders, and they have been able to skim a % off every trading order that goes through that is not specific in price. Conditional trades are especially vulnerable and these are used by big funds. Goldman Sachs is just another tax man and Warren Buffett is one of their shareholders.
Obama is introducing a bank tax to offset this skimming as he knows he cannot stop it. But will any of that money come back to you? not likely.
The outcome of all this is that there will be very few long term investors as we do not know when the next banking failure will be.