The AP is reporting that Paterno will step down at the end of this season, which would mean three more games and a bowl. Joe (or someone close to him) has finally decided that his position is untenable, and there's no possible universe in which he would be allowed to coach next season. But remember: this news is coming from the JoePa camp. The university could still fire him before Saturday.
Update (10:40 a.m.): Paterno's statement: "With the benefit of hindsight, I wish I had done more."