I sometimes feel that--if they were going to do Sins Past--they should have focused more on why Gwen would have sex with Osborn. She's overdue for a something-is-changed-that-you-always-thought-was-true storyline. That Goblin Kills Gwen thing is tired. It needs to be put to bed. The only way to do that is to change the character.
I know a lot of people canonize comic past, but in an ongoing narrative, this sort of thing has to be done now and then.