The Silent Camera app in the app store WILL SAVE PICTURES using the CM9 by MTDEV.Enjoy this info .It works for the back camera idk about the front camera.Must use serial shot to get it to work if you do normal picture you will get force close.
https://play.google.com/store/apps/details?id=soft.kinoko.SilentCamera
https://play.google.com/store/apps/details?id=soft.kinoko.SilentCamera