Sony Computer Entertainment America bossman Jack Tretton has gone on record to clearly state that there will be no price-drop for PS3 until at least June 2008.
In an interview with Game Informer magazine, when asked if price drops for the PS3 would be "as soon or as drastic as they were for the PlayStation 2," Tretton answered with a clear, "No."
The PS2 originally launched in the US in October 2000 at a price point of $299. The first price reduction on that machine, when the price was slashed to $199, was made by Sony in May 2002. Hence, if Tretton is to be believed, the PS3 is going to continue to set you back $599 (or the planned £425 in the UK) until well into the summer of 2008.
Tretton claims that the massive investment in research, development and hardware means that the PS3 is far "more difficult to cost reduce" than was the case with the PS2.