They wouldn't, since MS does not market well in Japan at all.
Both have their perks and flaws, and I do not wish to turn this thread into a complete Xbox 360 vs. PS3 thread by going into detail. Though I guess the original thread is already destroyed -.-

@Darthrat
I'm curious about Natal too, I can see it going either way at this point, but that's an interesting point you have there. 360 is doing MUCH better than original Xbox, and with all the bad Rep.

Wait, why do Sony fans have the burden of demonstrating why 360 doesn't sell in Japan?  It doesn't, yet other American products can sell amazingly in certain cases.  Sony/Nintendo loyalty may be stronger there, and there may have been more of a feeling of "who the fuck is this, now?" when MS comes in with 360.  Sales are still deficient there...what will any explanation get you?

1) RROD.
2) No(not enough) big exclusive games, that have Japanese appeal(PS3 had announced MGS4/FFXIII/GT5/HSG5).

Every time, with release of some Jrpg, x360 had spike in sales. But that was not enough.

PS2 was WAY MORE UNRELIABLE than original xbox and ps2 sold plenty worldwide. 

In fact XBOX 1 sold way less in Japan and it was MUCH MORE reliable than the ps2 soooo your argument is illogical.

Also, most of the inventions, nobel prizes, medical scientific advancements are created or awarded to Americans. 

YouR japanese superiority diatribe is extremely ignorant.

^Again, it`s not 1 factor.
It`s 3 factors/reasons together.

And PS2 wasn`t WAY MORE, that`s your imagination.

@zorroX - Sony has lost about 6 billion on the ps3 in only 3 years.

Sony's ps3 has lost more money in less time than ANY CONSOLE IN HISTORY!

That alone should be enough to dispel your Japanese superiority ramblings

Yeah it's kinda silly when everyone's like 'PS3 is on top this week!'.
It's also silly at how PS3 fans are SOOO quick to judge MS and Xbox 360 as an inferior product, but tend to avoid/conveniently forget about how much Sony is on the red over PS3.
So PS3 > Xbox 360 to them (and I can see it either way), but there's NO way you can say Sony > MS. Thus far, Sony has made some poor choices that has cost them too much, versus MS, while being hated as a company, still manages to profit considerably.

@PizzaFaceGamer, 6 bln. $? Give me a link.

Also, because Sony is losing money on PS3, it should sell less in Japan? Where is a logic?

Again, PS3 is not going to stop selling. It`s going to make money since next year. So, that loss is going to decrease. GT5 and GT6 will alone bring probably... i don`t know. But a lot(500 mln.- 1 bln. $?).

PS2 was unreliable only in its first year on the market, wayyy before Xbox was launched in Japan soooo your argument is illogical.

http://www.hotbloodedgaming.com/2009/10/30/i-wish-i-had-4-7-billion-dollars-to-lose/

When you consider the ps2 and psp were profitable sony was still reporting billion dollar losses which means the ps3 wasted all the ps2 and psp profits as well.  The REAL LOSS of the ps3 is probably 5.5-6 billion dollars - NOT SMART!

Also,  looking at the chart on the link.  Sony has lost more $$$$$$ on the ps3 than they ever made on ps1 and ps2 - NOT SMART

http://www.joystiq.com/2008/08/19/the-sony-reciprocal-ps3-losses-surpass-ps2-profits/

1 product (ps3) = entire history of gaming profits erased in just 3 years.

PS - Sony said ps3 was going to be profitable last year AND the year before as well.....sony's PR is like a broken untruthful record.

http://www.cinemablend.com/games/Kaz-Hirai-Hopes-PS3-Could-See-Profit-In-08-09-Fiscal-Year-8191.html