Interesting question. I'll decide to predict where PS3/Wii/360 will end up.

We know that the PS3 is tracking ahead of the PS1, and the PS1 did over 100million, however we also know that the PS1 shipped 19.3, 21.6 and 18.5 million on its 4th, 5th and 6th FY so it should start tracking ahead of the PS3 soon.

Anyways, LTD we have:

PS3 = 33.5 million
XBox 360 = 38.7 million (39 million rounded up from Greenberg)
Wii = 67.45 million

YTD
PS3 = 10.8 million (forecast = 13 million)
360 = 8.5 million (forecast not given)
Wii = 17 million (forecast = 26 million)

Let's say that Wii and PS3 meet their forecast for this year and that the 360 ships another 2 million this quarter, that would mean:

PS3 = 35.7 million
360 = 40.7 million
Wii = 76.45 million

Now from here on out will be very tough to predict how things will play out, but I'll give it a shot. I expect

MS = this fall comes out with Elite 250GB 360 bundled with Natal and a game for U$300, Core 360 with natal and a game for U$200. Those will be the standard SKUs and all other SKUs will be phased out. After that I expect another price drop in 2011/2012 with an introduction of the 720. By 2013 they'll probably stop producing 360s altogether. I do not expect a 360 slim. IF MS wants to be really aggressive with pricing, knock U$50 off the bundled prices I gave above.

Sony = I'm confused on Sony because they said they'll lose money for another year but they already filled for another FCC on the HW - which supposedly improves HW cost savings - so maybe they're counting on another price drop already? I expect this fall comes out with Arc bundle 250GB PS3 and Eyetoy mini game for U$300, and the 120GB for U$250. If they want to be aggressive, they'll bundle the 120GB as well. 2011/2012 will see it for 199/249. I wouldn't put it past Sony to release a slimmer version of the PS3 with SSD drive instead of HDD.

Wii = Drop price if and only if PS3/360 start to threaten it like the PS3 slim did in early september. I do not expect a Wii HD.

With that said I think the PS3 will possibly squeeze by it, but it'll be after the PS4 is already out, the 360 will be just shy of reaching the milestone and the Wii will maybe possibly pass the PS2, depending on how well the PS3/360 sell after their price cuts/bundles this year.

The only problem is, and it's a long shot...

What if the Wii successor is out either this year or next? Sony and MS have both stated how they want this gen to last for a long, long time so i doubt we will see anything from them for a few years yet, especially if Natal and Arc both sell moderately well.

Nintendo have constant rumor's of new hardware being revealed, and don't seem to talk about how long they want the Wii to be on sale for (i haven't seen anything anyway).

It could severely drop Wii sales as Nintendo focus on the Wii2, and could keep Wii from hitting PS2-like numbers.

yes it may be unthinkable, but one only has to look at the growth of the market world wide this generation vs' last generation the Wii is in 38 countries world wide, how many was the game cube in last generation?, not 38

just look at the xbox360's market penetration :

the first xbox was only released in limited areas vs's this generation now 21 region's for the xbox360.

the market can sustain the growth. I think that has more to do with the advancement of technology as a whole even 3rd world nation's what would have been no way near the advancement of technology now with thing's OLPC:

http://laptop.org/en/children/index.shtml

the world is getting smaller for communication and technology unlike 10 year's ago who would of ever thought of the Netbook reaching a price of $100.00 or less, yes that's quite a bit of money  in some place's of the world but also there is many areas that now have this technology in those countries that many thought there would be no way because of the econmic's there but yet there it is.

yup, but on the same token so what if it's out, did that stop the DS lite from selling when the DSi was released?

nope...change the color and yet you still keep selling the unit's. just look at Nintendo's history of selling system's.

that just mean's they will just keep selling the Wii.

DSi isn't a whole new console, it's simply a hardware redesign.

What i mean is, a whole new console. New specs, new games... The lot.

that seems inconcievable!

Why would the fastest selling gaming system ever, possibly consumer electronics product ever get a successor before its competitors

Expect to a see DSi type successor with possibly a built in hard drive & so on

but I simply cannot believe a wii2 can be a year or two away or that it will release before PS360's next gen system

Hey, prettyt much anything is possible even if it does sound quite stupid

Perfect example, thank you. 

It can be clearly seen, as demand dramatically dropped after the fifth year. 

Possible? No.
Impossible? Yes.

but if you look at that the DSi has no GBA slot the DS lite does, the DSi has 2 cam's inside the device the DS lite does not even have 1 cam.

there is more that seperates the two system's that make them more unique DS system's than counted as the same.

like the PSP and the PSP Go

PSP 1000 had only 32MB's of ram and every PSP until the PSP slim had that same 32 MB's of Ram though the slim of the PSP had now 64 MB of ram

where as the PSPGo now add's the Bluetooth standard, but also the 16 GB flash storage. smaller screen , yes the loss of the UMD drive is what the old PSP's have over the PSPGo.

these are no longer the same unit's.

now imagine the game top set boxes doing the same, like it's already happened already.

the first xbox360 had no HDMi now it does, the first PLAYSTATION 3 has A card reader but since you can add a number of standard USB card reader's

they removed it out of the PS3.

That's how many SKU's have we seen this generation?

I do not think we have seen the last of them