In my observations of console sales for the last say six years, there has always been 1 console that is far out in the lead and usually has the most momentum. Sales for the competing system/s catching up for the most part happens during the busy season. For example, during the month of May the week of the 11th, the PS2 had a hardware advantage over the xbox of 7,384,671 in the Americas, and sold 55,124 units, the xbox sold 26,015. The xbox would never gain enough momentum to ever catch the ps2 but did outsell the ps2 during 2 of the biggest weeks in Dec 2004, again to loose momentum at the end of January 2005. This spike in sales was in part due to the release of Halo2 witch killed Metal Gear in sales but wasn't enough to fight off the onslaught of games the PS2 had going for it.

In another example of hardware momentum, the xbox in Sept of 2004 had a hardware unit advantage over the gamecube of 1,183,096 in the America's. The week of the 25th the xbox sold 63,012 and the gamecube sold 27,506. 

Looking at the Others market we can take an example of week 4, 4/30/2005 (A slow week). The xbox had a hardware lead over the gamecube of 2,526,847 units. That same week the xbox sold 17,145 units and the gamecube sold 8232, and last but not least the ps2 had an astronomical hardware lead (kinda like the wii is on its way to having), it sold over 100,00 that same week. 

This generation the ps3 has an insermountable lead over the 360 in Japan, witch I feel is its only hope to ever catch up the 360's mammoth lead in the America's. The Holiday fueled momentum it has in Others is not enough for the ps3 to usurp the 6+ million lead the 360 has in America. Also take into account that Microsoft is not stupid, they know the momentum they have already made and have already publicly stated that Europe is key battleground. http://www.gamesindustry.biz/content_page.php?aid=31694. 

 Last but not least, price must be taken into account. If we are to compare this generation to the last, the wii is the ps2 of this generation the ps3 is the xbox and the 360 is somewhere in between. The wii is a hardware force and has momentum that may never slow down, and will be able to go toe to toe with any of the next gen hardware as far as price.  The 360 in America is a Software force and ain't to shabby in Europe either with an almost comfortable lead over the ps3 in the meantime. Microsoft will milk the 360 at the price that its at now to continue profiting on software sales until the last minute, then BOOM price-cut, (and the next one might actually be a pretty significant price cut). Unless blueray and cell architecture get stupid cheap Sony won't be able to compete on the price side of things if 360 hardware is cut significantly. Time will tell, but at the momentum the ps3 has, as of now, it'll be a looong time before it catches the 360.

Too toot my own horn, I forgot to put in the fact that the ps3 has already had several price cuts just to get to where its at in sales now. This doesn't bode well for Sony.

The kicking PS3 is giving XBox360 in Japan will only get bigger. The PS3 will beat out 360 in Others, the name brand is just too strong. Look at the software, it is selling more with 1.6 million less consoles sold

 and yet the PS3 is STILL more expensive and open to furthur price cutting down the road. Xbox 360 has also seen the release of its biggest flagship game. The PS3 saw releases of very good games, but none of them with the name power of Gran Turismo, Metal Gear Solid and Final Fantasy. Not to mention the arguably unjustified hype-train that is Killzone 2

 The 360 still has some big name releases, Fable 2 and  and SC:Conviction come to mind, but not as big as the aforementioned.

@passenger

Didnt the wii just destroy the stupid console history thing?

Realistically, how big of an impact did Halo 3 really have on XBox 360 sales? Do you really expect any game for the PS3 to have a more dramatic impact on the sales of the PS3? How much money has Sony lost to date with their expensive hardware and price cuts? Do you honestly believe Sony will continue to lose tons of money in further price reductions in the near future?

These are the questions which make the PS3 comeback unlikely ... The PS3's big games will increase hardware sales but will fall (far) short of producing any long term benefit, Sony doesn't have much of an ability to reduce the price in the near future and will remain out of the price range of the vast majority of gamers for quite awhile.

 Absolutely Leo-j, that why I mentioned them being a force. But one thing you have to look at is the fact that the wii did it in its first year, and Nintendo was smart enough to come in at mass market price with an innovative control scheme. The wii has become a triple threat, it cheap, its marketed brilliantly and it appeals to just about everybody except Graphic whores like me!

Why do people persist with the whole "MGS4 is a killer app" banter? The series has been seeing diminishing sales and its not something that appeals to the mainstream. The only place you see MGS being touted as such is gaming forums, especially ones filled with Japanophiles.

With MGS4 on the ps3 only, I feel Konami might be beating a dead horse with sales coming nowhere close to GTA4 Halo 3 or GOW, but if they put it on the 360 I think the demographic might react better. I myself don't care much for the art direction at all, to me its just weird. But the graphics are pretty good I must admit. I've never really seen any games come out of Japan that have good character development like Master Chief besides Nintendo's creations. Solid Snake to me is just not that cool, and the comedy in the game just sucks, but thats just my opinion.