xbox_360_core_system
Only Microsoft knows the real reason of cutting down the price of 360 for Japanese market. 158,654 units within a month is not a bad mark, then why the prices dwindle?

The cheaper version is already available in the western market as the Xbox 360 Core System, and now for Japanese market without a hard disk drive, this will be available on November 2 for 29,800 yen ($255), about 10,000 yen ($86) less than its standard version. It will be $45 less than in the US.

Via: engadget