I can't see it beating Halo 3. But it'll still be a beast in sales.

My guess is...

First week:

Japan: 70 000 America: 2.68 million Others: 890 000

Lifetime:

Japan: 150 000 America: 7.49 million Others: 2.71 million

But this is just a pessimistic guess. There's always the chance this will indeed outsell Halo 3 and it probably will, since I'm always wrong at these predictions. 

Seems achievable...it might actually knock Halo 3 off the perch as well.

10 million - 11 million for lifetime sales

I don't know what the first week #'s will be, but whatever it is...it's going to have people saying...well, it's a Halo game...so nothing is surprising, and how Xbox gamers are all Halo Heads...I think the Game is going to have EYE POPPING Numbers, the like of which will not be seen for a while...until the next Halo Game...lol.

15 million.. I think It will be a better overall game then Halo 3 and that will help sales. Plus Microsoft will advertise the hell out of it.

i don't know if it will beat out halo 3 or not, halo 3 was way overhyped and sold a lot, i know lots of people have made the switch to modern warfare now, it's really hard to say