I will throw this down. I will bet a week's ban that Goldeneye will outsell this game, and that local multiplayer, in addition to online, will be the reason.
I do not accept the bet (I know you've already retracted the bet anyway) on the ground that it is impossible to tell whether the difference in features is the deciding factor in greater sales of the two. This goes direcly back to your correlation=causation issue. You tell us sales do not signify factuality and then make a bet based directly upon it.
Further more, you accuse us of not providing any proof to support our claims without noting the irony. You have not provided any support for your claim either.
And the X360 and PS3 iterations do have local (and online) splitscreen multiplayer. I myself believe the Wii capable of doing splitscreen and even online splitscreen (Mario Kart Wii pulls this off) but understand the engine for the Wii iteration is done designed for it. Even if Treyarch wanted to include, they'd never have time to include it before launch.
1. Well I also realized it would be really hard to verify, if we just go by sales. But you should also realize you can't go by sales for the other assumption either.
2. I don't really have the means to do a proper statistical survey of customers. My point is that those that have the means don't seem willing to do so. Even if you can't, those that can should do so.
3. Well if the split screen would actually cause so much strain, even on those systems, why not take it out of those versions to ensure performance? If onine is so much more important, no one should miss it.
That wasn't a joke. From what I was told, that would be a sensible option to make the best running game possible.
I still say Goldeneye will outsell this, assuming the game lives up to the promise and has some actual marketing as well.