No way, will Halo 3 do 15m or anywhere near that amount.
Halo 2 did over 8m worldwide and was released when the Xbox had around 20m users.
Halo 3 has been released on the 360 with only around half that amount.
Don't get me wrong though. It will do very well, but I can't see it breaking over 5m anytime soon, and you can forget breaking the 10m barrier at all.
I reckon we will be looking at 5-6m maximum.

 Wii Play isn't even a real game.  It's just a good way to track how many controllers they have sold with a little garbage game added on.  It's basically a modern day Duck Hunt except this time the little game comes with a controller instead of the most popular game of all time.  

Uh 5-6 maximum? Both halo 1 and 2 did more than that and this one will definately pass both of those. Halo 3 will have close to 3 million by the time the first WEEK is over. You seem to lack the intelligence needed to post on these boards and be taken seriously.

Do you realize the 360 will also hit over 20 million users and halo 3 will still be around then? Do you realize Xbox had a userbase of about 24 mill and the 360 will be around a year longer than it and have a userbase of over 30 million easily? Halo 3 outselling Halo 2 is as close to a lock as you can come to in life.

Judging by the fact you think the 360 will only sell 12 million consoles this year, when it's only 900k away from that right now with 3 months left in the year, you clearly don't know shit about sales. Last year, without halo 3, with a higher console price, the 360 did 1.1 million in december in america alone last year. What is wrong with you?

If you look at the (recent) games that have sold in the 15 Million range (Nintendogs, Gran Turismo 3 and Grand Theft Auto) you will notice that they were all released on systems which were selling amazinly fast when these games were released, had larger usebases than the XBox 360 has, and sold to a very broad audience.

I could see 8 or 9 Million, but to get close to 15 Million Halo 3 would have to be bought by 50% of all XBox 360 owners; which is unlikely and made even less likely when you start factoring in game rentals, piracy and used game sales.

Mr stickball don't make insane predictions if your not John Lucas and you do not predict something for a Nintendo system. Didn't you know that?

Well, I'll back ya up. Halo 3 has a much bigger hype in US than Halo 2. I expect higher numbers there. And the 360 has a better chance to get a decent user base in Europe, leading to higher sales. I say 15 Million is very high, but not impossible if everything you said kicks full in.

Halo 3 is the greatest multiplayer FPS experience, it is no denying, I love it.

Is it your second Multiplayer FPS?

There is nothing drastically different in Halo 2 that wasn't done in Unreal Tournament, Counter Strike, America's Army or Quake 3 way back in the day ...

I'm not saying it is bad but come on.

That's a pretty bold prediction and I need to disagree.

For, three primary reasons.

First, I think there will be a repackaged and shipped as a "Trilogy" box with Halo 1 and 2 sometime in the future (Christmas 2009?). So, Halo 3 will cease to ship as a product at that point because you will get all 3 for the same price. It is far too, tempting for Microsoft to do this and if you could port the other two Halo's and give achievements it would instantly sell millions to the Halo lovers out there.

Second, I think that we are just starting to see what this generation of games can offer, and to say nothing coming out will rival it is too bold. There are a lot of big budget games coming out and will continue to come out for this generation. Many started development before Halo 3... Also, there are so many games shipping now and in the future that Halo 3 has way more competition to sell the 15 m... Mario Kart was stand alone literally, with no competion at all.

Third, it has an M+17 rating so a lot of people will say no to it on that basis alone... For a game to do 15 m I think it would have to be E rated...

I does have a shot. But I'm only betting on it breaking 10 mill. It really does depend on how big the userbase gets. It has plenty of hype and it will be the game to get with the system. It will be easier to predict next year. For those who think its impossible for any game look at Pokemon d/s the game is already at 10 million with a 40 mill user base, and it's still flying off shelves not even past a christmas yet, you know the thing will break 15 million.

But I think Halo's biggest problem is Japan. Mario/pokemon/Nintendogs has universal appeal japan loves these games as much as anyone. Halo will sell in japan well for the kind of base it has, yet it probably won't break a 100,000 there, so getting all these millions will be the rest of the worlds job, and mostly Americas, that has to be one heck of an attach ratio. But again it comes down to how well the system sells here on out.

I agree about Halo 2 though, if released a year earlier the game probably would have saw another 1 or 2 mill in sales, there is nothing that kills game sales like a dead system.

No. It's not going to reach Nintendogs numbers, just forget about that. Well more than half of Halo 3's sales will likely come from the NA market. It's not as huge in Europe, and it's insignificant in Japan. I think it'll do over 10 million, but even that will take a few years or so probably. To get to 15 million WW I think it needs to sell at least 8.5 million in the US. Plain and simple the game is not going to sell better than GTA San Andreas on the PS2, no way.