Actually it is stupid to compare two unrelated games. Mario on the NES or SNES sold over 40 million. But comapring GT5 and Halo Reach, GT 5 doesn't stand a chance. Just check the pre-orders. GT5 has 11 weeks left, and it is on 160,000 pre-order. Halo Reach surpassed teh 400,000 mark on it's 11 week left for release. Now it has 1.25 million pre-orders, which has surpassed COD MW2 4 weeks before release. I don't see GT 5 selling half as much as previous GT games. I would say though Halo Reach has a good chance to surpass Halo 3 in sales.

I dont think some people understand why GT and Halo sells. The same rules that govern why Halo:Reach will sell 10 Million are not the same rules that govern why GT5 will or will not sell 10 million. They arer 2 entirely different games and their sales are decided by competely different parameters. The only thing tying them together is that thery are the flagship titles of their repective companies and fanboys would like to see the game they support succeed while the other one fails.

And to the person that said "GT was never bigger than Halo" and used attach ratios to prove his point. So because the PS1 and 2 sold 100 million consoles a peice means that GT needs a 25% attach ratio or higher to be bigger than halo? it just goes to show that the userbase back then was diverse. Using your analogy it would mean that during the PS1 and PS2 eras each GT game would have to sell 25 million copies in order for the series to be bigger than halo, its not plausible. As far as which gaming franchise is "bigger" just look at 24hrs le mans races, notice on all the cars there's a GT logo at the top of the windshield? Not to take anything away from Halo but, GT is a brand, Halo is a Game, even if they sell the same amount, they sell the same amout for different reasons.

I'm not a owner of any HD console.

Reach will destroy GT5 in sales.

GT series have been around for a lot longer!! Also around a time when market saturation was much much much weaker than it is now. Halo competes with AAA games like Call Of Duty, Battlefield, etc, etc!! What did GT compete with back then? Seriously...what a waste of your time making such an unfair thread.

lol, 3 games barely outsold 2 games. dominance looks different imo.

You are looking at pre-orders in NA. Halo 3 sold 8 million copies in NA, with only 3 million for the rest of the world. Nearly 3 quarters of it's sales come from NA alone.

GT5 prologue sold just over 1m in NA. So roughly a quarter of it's sales coming from that region.( Not including DL sales.)

Well NA is a big part of both series.  If you look at the NA sales for Gran Turismo according to Vg chartz it makes up about 36% of the series total sales.  Europe makes up about 46% and Japan makes up about 18%.  With each main GT title NA sales are always over twice as much as Japan. 

That means that those NA pre-order numbers are very important since over a third of GT sales come from the region.  Everyone knows that Halo Reach is going to get it's usual massive numbers in NA because the fps is king there all you have to do is look at the pre order charts each month or the bestselling titles each year. 

The big question is can GT get the numbers it needs in the Americas to keep pace with Halo judging by the pre order numbers it's not looking too good we will have to wait and see how it sells after launch.  But right now it looks like PS3 owners are going to overlook it and buy COD Blackops and MOH first. 

Why don't you make a comparison of games that are relatable?

GT is a racing series while Halo is an FPS series. Also, GT sells in Japan unlike Halo which is not geared towards the Japanese.

Why not compare apples to apples? Resistance to Halo. Forza to Gran Turismo.

Making comparisons like this is asinine, and it's obviously very fanboyish.

PS3 doesn't have any other game besides GT5 that is expected to sell as well as Halo Reach. When comparing top selling games it doesn't matter what genre they are from. The are both coming out this fall and will be the biggest two games of the season. When it comes to sales they are apples and apples.

Really the best comparison is to compare this gens numbers....but that unfortunately won't work since there isn't an actual GT game out yet (not to mention by the time GT5 comes out Halo will have already had 2 big releases)