I doubt it will maintain a 33% attach ratio, but I think it should reach 7.5 mil and beyond this lifetime.... I mean at the rate PD makes game this will likely be the only true GT game this gen, and the game doesn't really get dated the way many other franchise does.

Top 3 Gran Turismos > Top 3 Halos.

GT wins.

Yeah i know the past GT has been far bigger but i wanted to compare on todays systems, the HD ones. 

Yeah, and we don't know that since Gran Turismo 5 hasn't released.

We're only allowed to compare current generation games, but Gran Turismo hasn't stepped up to the plate yet. What the hell are we supposed to do? Guess?

It was a thought through prediction, i stated everything in the OP.

There has been alot of talk recently about which is bigger and i gave my input. Whats the problem?

I guess that neither game will have a 33% attach rate by the end of the generation. Gran Turismo has never had an attach rate that high, and Halo 3 has a 31% attach rate (which is dropping week after week). All we can do is guess, but we have nothing to work with.

Well the title of your thread is misleading.

Halo is synonymous with the Xbox name. It will always have a high attach rate.

Sales would be for bigger franchise overall, ratios would be console-relevent.

ok, well i tried but failed....