I expected more of a battle to start alongside Collins at safety, but Morgan Burnett has had two solid preseason games in his return from a torn ACL. He had a couple big hits against the Browns, and he almost grabbed an INT against Kevin Kolb. Charlie Peprah had a good game against the Cardinals, but the coaches want Burnett and he's played like he's earned it.
CB Josh Gordy. I'm not exactly sure how far up the depth chart he's risen, but he had a big game against the Browns (1 INT and 1 sack) and got some playing time with the first team defense. He played as much as CB Sam Shields, who got his first preseason action against the Cardinals and allowed one touchdown. I can't believe Gordy has moved ahead of Shields, but I could see it happening.
Undrafted CB Brandian Ross missed the first preseason game after a strong showing in the Family Night scrimmage. He got burned on one play, but then made up for it with an INT in the end zone on the same drive (though he's got to learn when to take a knee). His playing time is similar to former 2nd round CB Pat Lee. Those two might be battling for a final CB spot, or maybe they've both already lost out to Gordy, but I think the Packers need to keep either Ross or Lee.
And CB/S Jarrett Bush still had some playing time with the first string defense, though he got beat on a couple occasions and missed at least one tackle. He does seem to be Woodson's backup, so it's essential that Woodson remains healthy.