I just wanted to add our experience, and preface it by saying that I am sure it is not the norm, but it obviously can happen and has changed how we do things.
This past spring we did a split stay CR/BWV. When we checked into the Contemporary, they asked if we had a laptop, we said yes, and they put it in their special room for computers and valuables. Everything went fine and it came to the room with the rest of our luggage once our room was ready. When we went to have our luggage transfered to BWV, we again told them about the laptop bag so it would be stored in the appropriate location until it was time for them to do their transfers (we checked out early morning, and they do transfers early afternoon). We never saw that bag again. In addition to the laptop, we had camera equipment, our keys to our minivan that was parked at an airport 3 hours from our home, and several other items, adding up to around $2500. We will never leave anything of value with bell services again. Nearly every afternoon that week was spent trying to track down that bag, dealing with WDW security and filing police reports and claims, and trying to figure out how we would get home once we reached the airport. It was all a huge hassle, and certainly put a damper on our vacation.
Just wanted to give you a heads up. Like I said, I'm sure that what happened to us doesn't happen often, but it does happen, despite how many times the manager at the BWV told us it doesn't.