western English speaking cultures greatest contribution to video games is the FPS genre. From quake and goldeneye to halo and COD, Americans and English have a genre of their own outside the dominating video game influence of Japanese design. The Xbox was the catalyst for a lot of PC-exclusive devs from the 90s to create games on a format that is traditionally dominated by Nintendo, sega, capcom and squaresoft and there obviously is a huge market for it in NA and UK.

Bolded for truth.  This is why the Wii U is going to have such a tough time this coming generation, because it essentially does what the 360 (and PS3 to a lesser extent) has already been doing for the past 2-1/2 years... giving the expanded / casual audience an HD alternative to the Wii, not just for gaming but for movies and TV and other entertainment too.  Especially considering the fact that right now pretty much all Wii U games are on par or even below the visual standards set by PS360, and many would-be purchasers have already started to notice this.

Nintendo is going to have to really push the whole TVii feature and other entertainment hard if they wish to stave off competition from Sony and especially M$ this coming gen.  I've no doubt they'll do well in Japan as always, but the US market is totally up for grabs this time around, with M$ clearly the frontrunner heading into the next gen.

Microsoft carved out the niche as THE console of choice for FPS titles.  Throw in third-person shooters also.  For exclusives shooters, you have Halo and Gears of War.  And the place to place to play them is on the 360.  FPS is popular in USA, so Microsoft gets the nod.

Excuse me? How is it more popular ? please explain?

Halo, Gears, Forza need I go on. Their exclusives are amazing, and Americans get it.

The fact that it is current sales - not from an earlier launch - I think really doesn't matter this much time later.

I think it is because you can get experiences on the Xbox 360 that you can't on any other system. A few years ago, many of my non gamer friends all started getting Wiis - as it was this unique new experience. Now we have Xbox with Kinect - and they are now talking about that. It's fun, innovated, and exciting.

It can play most of the same games the PS3 plays, and it's movement works better than the Wii in many ways. Plus it's an all in one, easy you use, streaming system. Yes, it would be nice if it had a Blu-ray player, but they are so inexpensive these days it doesn't really matter. And personally, I prefer digital, and the only time I get a blu-ray is when it's so much less expensive than digital.

And I think the general public doesn't really understand what the WiiU and tablet is all about.

Well in this instance it means it sells more!

Just look at the charts. The 360 has sold 42 Million in NA and PS3 has only sold upwards of 20 Million.

Microsoft monopoly of the American market, they have a far bigger stake in the media than Sony.