Well it seems as if the key issue in deciding wether a cat should be indoors or outdoors is how safe it will be.

I like to allow my cats the ability to come and go as they wish. This means that whenever I move the priority is to find a property that is cat friendly, ie. I look for a house that does not have access from the back-yard to the front of the house which means I can let the cats out the back without them making it to the front of the house and therefore the road. I also make sure that access from the back-yard to any roads is not readily available. All these considerations may make looking for a house difficult but it keeps my cats safe and is well worth the effort - and I'm sure we all agree on that!