I'd guess there are a few reasons behind the lack of price-cut:
- the exchange rate. (they probably purchase components in non-$ currencies..)
- having to design to fix the RRoD issue, rather than to optimize the console...
- the console is already fairly well optimized, cutting costs is hard.
- if they cut $200, they'd be giving them away.
I'd guess the exchange rate is probably the main cause, along with a desire to make a profit.