re: about the skepticism about monthly DLC (especially for tracks) consider the two following qualifying items that even if not mentioned, are a very likely reality...
1. We asked for it, and we seem to be eager to spend more money on the same amount of new content. PD were bigger than that. They wanted to give us a full game and maybe add stuff later (though, they DID promise). But we have asked to be nickled and dimed. Now, all they have to do is withold content and release it monthly. That doesn't requier all the dev of the new cars we've seen added in DLC since GT5's debut. It saves them headaches AND makes more money than they othewise would have made with GT6. remember, we asked for it.
2. "Montly" was never qualified with a term-length. "Monthly" could merely be for the first several months post-release and then go down to "quarterly" after that.
#1 above also lets them have a little more time to finish some things not quite ready for GT6's release. So as long as they get the full core game finished, the amount of content finished doesn't stop them from releasing.
It's almost an incentive to not work as fast... but again, we asked for it...