That's $18 on PS3 hardware alone (most likely along the lines of what jarrod said). Does not take into account marketing, inventory, shipping, etc. to my knowledge.
"Sony loses about six cents for every dollar of PS3 hardware sales."
Also, as others said, only 15% reduction in costs by March 2011 means the PS3 will still cost ~$270 to make... The likely hood of a price cut before Fall 2011 is looking pretty slim to none unless they want to take another substantial loss on hardware.