In reply to Alpenglow:
I think the best way to carry a compact camera on climbs is to get an appropriate-sized chalk bag and carry it in that on a waist belt. Or in a padded case of an appropriate size if there is one, again mounted on a waist belt. This way, the camera can be pivoted around the waist and out of the way of environmental features, even in chimneys.
Tie a loop of thin accessory cord through a camera strap eyelet. When the camera is removed from the pouch, clip it to an over-the-shoulder sling.
I think any method (such as clips mounted on pack straps) that fixes the camera in a single location on the body is going to be a bad idea in some circumstances. Plus there is the issue of removing the pack and banging the attached camera.