Didn't hear about the collision detection Bob, I hope you're right though.
There will be interior updates in the GTRs if not all cars, and "updates" to the AI. All the rest is just rummors.
Knowing Scawen, I think he will just go all out for the AI and make it so every part of them works rather than doing a halfassed job just so they can leave the pits and that is it. I'm sure he'll give them new lines, more intelligence (meaning.. more attention to what is around it), and pitting most likely off of some base F12 menu pit settings.
That can be all up to criticism, that is just my guess as to what Scawen will pay attention to mostly.