Seriously, the amount of arrogance and bullshitting is through the roof in here.
People are stating their opinion as if they were facts, with nothing (read: nothing) to back their claims. It's pitiful actually. It looks (read: looks) like a fanboy war all over again. Halo or Gran Turismo will do better because it will do better is basically the only argument I've read here. Stating the attach rate is ludicrous. I could do my own spin and state that when Gran Turismo 3 came out, the install base was nowhere near what it is right now. GT3 came out in 2001. A game usually sells the better of its number during its first 2 years. At this point in time, the PS2 install base was at roughly 46.5 milion yet GT3 still sold over 14 milion. You could debate that the game sold a lot even passed it's first 2 years, But anyone following the sales Chartz will notice a game barely have any legs passed the 2 years - 2 1/2 years mark (there are few rare exceptions).
Now, the PS3's current install base ir roughly 10 milion below what the PS2 was 2 years after the release of GT3. But an other factor comes into play. Hype. From my observation, the hype for GT5 is at least similar if not above the one surrounding Halo: Reach. Similar because both are the most popular and lucrative first party franchises for each respective console, yet different because in GT 5's case, it is the first main entry in the series on the console and the amount of new features and polish in that game compared to its predecessors completely dwarfs Halo: Reach's.
Now, when people talk about the attach rate, it should be taken into consideration based on when the actual game was still selling itself. GT4 didn't sell as well as GT3 and there are many potential and reasonable reasons for that. For one, many could have seen it as not big enough a step up to warrant the purchase of it, having spent the countless hours of gameplay on the first outing of the console already, and not willing to do it all over again (the game still sold over 10 milion copies anyway). It could also be that the franchise had become a bit stale in the mind of gamers and they lost interest (it still sold over 10 milion copies). It could also mean that because the PS2's install base is so huge, so is the diversity of gamers preferences going to be huge. Or, it could be all the above combined or any other speculative reasons I didn't brought up here.
You can play with numbers and speculate all you want just like I just did. But to state that one is definitely going to sell better than the other is nothing but pure speculations. When you say your opinion is right, or state it in a manner that points in a similar direction, when talking about something that has yet to be proven right or wrong is completely arrogant, and immensely childish.
@Selnor: Just like you to pretend to know every single persons who buy the Gran Turismo games. ¬_¬
