That $40.00 fee for a used game crap is more than likely just a dumb rumor. No one is really going to pay $80+ for a used game and microsoft knows that. I think the fee will be some where between $.99-$5.00.
Microsoft wants the used game industry out of the way, so I could definitely see them charging a $40+ fee for a used game, even Sony wanted to do the same but they so far have said that they won't.
The ongoing rumor with PS4's online is that they'll have a tiered system....basic online would still be free but the better features like cross-game chat, video sharing, cloud saves, discounts, etc. would require a subscription.
As long as it's optional, I'm good.
So it will be the same as now