polezo on 10 April 2009
Not God of War III because it doesnt have a big enough showing in Japan. Final Fantasy xiii could have a chance, but the comparison would have to include skewed dates, since Halo 3 released worldwide on one day, and FFXIII will be out in Japan far before it hits the west. FFXIII also multiplatform so its not quite a fair comparison.
One you didn't mention that could beat halo 3's sales is Gran Turismo 5. If it hits with a high enough install base for the PS3 (in Europe especially), it could maybe eclipse Week 1 halo 3.
