I also recall there being around 30 issues for Angular 2 Final on github milestones the day they announced the release, but they were mysteriously gone in the afternoon.
It was the TypeScript team that invited the Angular team to build Angular 2 on top of TS (at the time, they were planning their own JS dialect called AtScript), so I would be surprised if they later changed in a way that seriously broke compatibility with Angular 2.
I also recall there being around 30 issues for Angular 2 Final on github milestones the day they announced the release, but they were mysteriously gone in the afternoon.
Angular 2 Final seems to be anything but.