Saying a player will be a "cap casualty" can be a loose term. It is really more of simply ROI (Return On Investment) than anything. If a team likes a player enough, they will pay what it takes to keep him. Other times they will restructure to keep them. So, calling them a cap casualty is a way of letting them down easy.
That being said, here are a few of the more notable players who are expected to be "let down easy" or allowed to seek employment elsewhere.
C Dominic Raiola, Lions
LT Jordan Gross, Panthers