To answer the question, why sell at all in Japan? Because they need Japaneese developers, and try to atleast get some of the 10m units a year that Japan sells in consoles.
It'd be a very big shock if the 360 did go down to 3k for the week (I would more assume somewhere at 4k). However, judging on last year, it's possible....Even though it'd still be up 50% over last year, and be the new low for the 360 since the core was launched.
Having said that, I will already re-iterate what others have said. There is ONLY ONE reason the 360 isn't doing even PS3-ish numbers:
The 360 does well in the US not because its a US console (the PS2 did far better and it's Japaneese). The country that makes the console is irrelevant. However, the country of manufactures games do come in to play.
The 360 has a very weak library for Japanese games...Similar to what the PS3 is (but the PS3 has the Sony brandname & more J-centric games coming out).
Blue Dragon sold 80k it's first week - 30k more than VG5. DoA4 was similar. Both are very J-oriented games. This proves that games that focus on a Japaneese audience can do well on the 360, and it can move hardware IF there are games that improve the Japanese library.
Look at the top 5 list of games that sell on the 360 for last year:
Blue Dragon - 119,750
DOAX2 - 57,500
N3 - 53,250
Dead Rising - 51,500
DOA4 - 43,000 (105k total from Dec 2006)
Lost Planet - 41,750
NONE of those games were made by a US company. None. Although sales #s like that are weak compared to other systems, it shows that games made by Japaneese companies do well....Considering the user base. If MS had about 25-30 decent titles by Japanese companies in a year, the 360 would easily do 1-2m units per year. However, that might never happen. Mistwaker will do well to help the 360, as well as Capcom and maybe more Konami support, but if the 360 doesn't garner support from Japaneese studios, it'll never do well. Western games just don't do well in Japan (on average, some games do well). Yes GoW is the #1 game in Japan on 360, but at maybe 60k units, I don't consider that monumental, expecially how it's doing elsewhere.
yea they should leave Europe and JAPAN now............and ofcourse after MARCH they would be bound to leave US with cartoonistic HALO 3 (lol) and watered down processors and 2$ dvd drive