I glad no one was foresight to avoid writing "isn't that just Modnation"......every other post has been plagued with those comments -_-.
I think whatever team is developing it, they would have learned from the mistakes of MN, which means don't expect long loading times. And as much as it will be about customisation, people will need to see brilliant kart and track designs already in the package. Hopefully the majority of sony IP's (in Sack form) with be in the game from the get go, as opposed to DLC or relying on others to make them. Interesting and well considered power ups is also a must!
I agree that there should be official forms of Sony's major franchises/IPs straight out of the box, instead of relying on DLC or the modding community to create them (I still think the community will offer their own versions of Sony's characters, though, even if they are included).