There's a big difference between arrogance and stupidity. If Sony believe they can sell PS3's at $600, and no-one buys them, they're not going to be stupid enough to keep the price at $600. They'll have to drop the price to sell any units, or otherwise just give up on consoles because they refuse to sell their console for what people are willing to spend on it.Sony is going to keep being arrogant thinking they can sell consoles cause it has the Sony name on it.
As has been mentioned elsewhere before, within this year Sony may well have shaved as much as $200 of the cost of PS3, with 65nm and BluRay improvements. If the machine isn't selling, a drop of at least $100 by 31/12/07 is likely IMO.