The way I see things, the most popular genres in each region are..

Japan - JRPG's

America - FPS's

Others - Racing

This is my reasoning for why even Mediorce JRPG's like Infinite Undiscovery and above average ones like Tales of Vesperia have strong releases in Japan.  This is also why Halo has sold more than half its units in America.  And this is why Mario Kart Wii manages to sell 90-110k units every week.

Why can this make or break a console?  In short, if your console lacks on any of those 3 genres, you'll likely NOT be the marketleader(by a big margin).  The Wii may be the marketleader now but if it doesn't get quality FPS's, it might lose America to the 360.  Also if the PS3 wants to stay dominant over the 360 in Japan, it needs some JRPG's(Final Fantasy XIII namely).  If for some reason FFXIII becomes multiplatform in Japan, I see the 360 selling at least 2 million in Japan by generation's end.  You may be headed but you can eat enough marketshare to make a difference.

Just my thoughts.    

I realize you are talking lifetime sales, not just LTD, but I feel the very examples you cite are proof that this theory is flawed. Wii and PS3 have done well in Japan despite a lack of JRPGs. Wii was doing well in others when its best racer was Excite Truck. Wii is pulling away in America with a lineup of FPS that only the most hardcore wii fanboy would defend.

I totally agree with you that the genres you cite are most popular in the regions you link them to; but no genre is so popular that it alone defines the success of a console.

What shooters did the PS2 have? I thought the Xbox was the shooter console, and it was far from the leader in America.

Anyway, I'd have to disagree with your reasoning. The games often follow the success of the console, not the other way around. Just take a look at the DS in Japan, by far the fastest selling system ever there. JRPG's had nothing to do with it. If the Wii somehow never got any shooters, it would still dominate America.

I'm glad I've been proven wrong. I still think the respective genres are important to the respective regions.

The Wii kind of crushinates the entire idea.

Ironically...

Wii is doing best in America despite having almost no shooters.

doing Excellent in Japan, 360 doing the worst even though it has all the JRPG's.

Others: All Wii has is Mario Kart, destroying competition there too, 360 and PS3 get all the racing games.

So....no.

They're important and profitable, but not definitive.

I prefer to think of certain genres more as a trophy or, in some cases, a victory lap.