It was only announced a few days ago, who knows when it will come out, i though Halo Wars was the last game.?

After Halo 3 I don't care about Halo 4. Gears of War 2, now that is where its at.

well if no other great shooter is released on the 360, then yes it should do well. But one thing i have realised with Halo 3 was that it was a very much over hyped. Not to say it wasnt good, but not as great as it was made out to be. with new and better games being released consistently and having to deal with the greatness GoW2 will be hopefully, Halo 4 might fail in comparison. I think Gears will become the 360 mascot and take over from halo. I don't see Halo being able to add more to the brand then what they already have.

did they officially announce halo 4 or just a halo game? i thought they said a halo game without any further details.

Even if its Halo 4 i am still not sure if it can break the records, there is just too many shooters coming so it will really depend on what other games will be released on xbox 360 around the release date and how good it can stand out of the competition. Also i guess we might see the effects of too much focus on that game genre in the way that some people are loosing interest in shooters.
but its all hard to say it might break the records, but it is in no way guaranteed we have seen often enough that a followup to a successfull game released on the same console did not automatically sell better even with the increased userbase.

The biggest letdown of Halo 3 was it's graphics (apart from it's AMAZING lighting). Whilst really good, the graphics just weren't good enough to fit with the hype.

Imagine a Halo 4 Gears 2-like graphics to show off, Halo 3-like gameplay and the same $10 million advertising budget.

THAT game would be easy to hype.

According to NPD, Halo 3 sold 3.3 million its first week, so I'd say with the larger install base, 4 million is very likely.

I think with the title "Halo 4" (for me VERY unlikely) it has a chance, but anything else will have less first week sales numbers than Halo 3

i dont know about 4m, Halo is the biggest franchise on the 360 but i dont see it selling that well week 1.

it could but it need to be release on sunday(thats when vgchartz week starts)

This is a silly question. I think the real question we should be thinking about is:

Will Halo 8 have good legs?

I mean, sure, it'll have great first day sales on the XBox 1080, which should have a userbase of ~45 mil by the time H8 streets, but what will the 5th or 6th week look like? That's what I'd like to know!