Halo Reach will sell the most...by quite alot.

Gotta see what will be shown at E3 first. -_-

I Would say Starcraft 2 or Zelda Wii if they release before or in November.
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Pokemon HG SS will own everything
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The vitality sensor game....

i dont think the 3 you mention will do that well... Halo will reach 10m top... mario galaxy too and GT5... will go more than that but with legs...

From those, Halo: Reach, but from all maybe StarCraft 2, or maybe just maybe if it's a hit with the masses then Zelda:Wii.
Ah, I forgot about, Pokemon Heart Gold/Soul Silver, that should give Starcraft 2 a run for it's money(most likely outselling it).

Halo Reach will destroy everything. If a sort of addon sold nearly 5m in just 4 months then a proper full title being billed as the last Halo game will sell huge numbers.

GT5 is debatable if it will be out this year. If it is then i still think Halo simply because GT series is most popular in europe and UK in specific. People forget the majority of sales come from here. GT4 sold 10m units in its lifetime. 6.4m of those come from others, mostly europe. More then Japan and US numbers combined. We love our racing games, it is just the way we are, we are all petrol heads at heart here.
But things are very different here in the UK now. Playstation is no longer the number 1 console. There are a lot of other games out there now, there is more competition.
Point being GT5 will not sell anywhere near the numbers for GT4 because that would mean 10m buying it, which is about 33% of the user base of the PS3. That is not going to happen.
If we look at the Pro-logue numbers we see the same pattern as before. 2m of its 3m sales come from others, mostly europe.
GT5 will sell loads here. The question is how much will it sell elsewhere? Japan numbers based on previous versions have been the lowest area. The last one only selling 500k there in its lifetime. Americas not selling that much more.
So realisticly you have to say Halo Reach will sell loads in americas, a lot in others and next to none in Japan. GT5 will sell a bit in Japan, a fair bit in americas and shead loads in europe.
So really it is sort of like putting Halo numbers in americas vs GT5 numbers in europe. Have to say Halo would probably win that.

I am a huge Nintendo Fan Boy (Pikmin Senior for you !), but i voted for GT5.

That series is huge, the X360 is already full of Action/FPS, there is little room for Halo.

With Mario Galaxy 2, i dont see it being as huge as Mario Galaxy 1 since most of the times, the second game of a series sell less than the predecesor.

yeah I'm with you on those nintend titles that could very well be the top exclusive of the year.  But of the three he lists it's probably between Reach and GT5 and with that it will probably come down to when they get released.  If comes long enough before it will sell more since it probably won't launch with as many and will have crazy legs.  Galaxy 2 will sell a lot more than most exclusives on the ps3 or 360 but not Halo or Gran Turismo

Why are people saying NSMB Wii when Wii Fit Plus is pulling ahead in weekly sales? This is obviously for 2010 games anyway/

It'll probably be Halo Reach unless you count Pokemon sales from Japan last year.

Well you have to bring in mind that Super Mario Galaxy was released on a smaller audience than now. Then of course you had other "Marios" that came after it. But this boxart looks more appealing. It really depends what kind of marketing goes behind it. I do believe it will surpass 10 million though. At this time well, IDK. Halo or GT5, well I don't know much about GT5, I'll say Halo Reach?

Yeah but Wii Sports will beat them all.