I appreciate the time and effort that went into these estimates, but they're far too optimistic (as others have said). In 19 months on the market, the 360 has sold 6.37 million consoles in America; you're predicting almost 5 million sales in the next 6 months? Appreciate the enthusiasm, but that's not going to happen. Somewhere in the 3-4 million range is much more likely, and will still make for a very good year for Microsoft.
Let me also state this: there's a zero percent chance that Halo 3 sells 7.8 million copies this year. 7.8 million! That's absolutely crazy; no game outside of Pokemon Diamond/Silver will do that well this year. There are only 10 million 360s in the entire world right now, and even Halo won't have an attach rate approaching 80%. Over the game's entire lifespan, maybe, but certainly not in a single holiday season.
The Japan predictions for the 360 are actually the craziest of all (150k sales in a single month?!), but with the numbers so low over there, it's not out of the realm of possibility.
You do realize that you are predicting no less than 14 different million sellers for the 360 this year, right? On a console with an installed base of only 10 million total.... umm, well, it's possible, I suppose. 
End of 2008 totals: Wii 42m, 360 24m, PS3 18.5m (made Jan. 4, 2008)
