I try to allways download to my computer as soon as possible as I am forever losing stuff. I also move stuff to CD as quick as possible incase I have a hard drive meltdown. diversefy everything. I lost a ton of stuff in Malaysia when I drowned my camera in saltwater and am still kicking myself in the butt becuase I could have taken my own advise and downloaded the night before, would have been a bad day instead of a bad week! I was diving at Sipadan and missed a ton of pictures like the one below!
Your best bet is to contact the airline and if you get it back
make sure to thank the person that returns it in writing to their bosses!