Yes, I too am reluctant to leave Facebook entirely. Rather than change my posting methods (resolutions change, etc.) I am limiting the amount of time any of the images I might care about stay on Facebook. I am also asking that no one who sees my image clicks on the "Share" button.
My reading of the policy is that once deleted from Facebook (this includes images that have been shared) Facebook no longer has the ability to use the image. I don't sell many images, so I am probably not at as much risk as photographers who make their living from sales. On the other hand, I would hate to not be recognized for my work.