I just have to chime in with something that happened on my Feb trip to WDW and going on the Disney Dream.
We packed 3 LL Bean rolling duffels, one for me, DH and DD each. When we arrived at MCO there were only 2 bags. The missing bag had all my clothing and toiletry bags for the whole family. American Airlines didn't find my bag until late that night, and it turned up in Guatemala! The 9 hours it was missing was horrible, would I have to replace all my clothing before we left on the Dream? I already lost one day at WDW (airline kept saying "it should be on the next flight from Miami"), now I might lose part of another day! Once the bag was found, it took an entire day to get to MCO and was finally delivered at my hotel at 10:30pm. I was very lucky I got it in time for the cruise and nothing was missing. I also lucked out that at the last minute I did a load of laundry before leaving and put a pair of my jeans and 4 pairs of underpants in DD's bag, so I only had to buy a t-shirt and toiletries to get by until the bag arrived. When my bag did arrive, it still had the 'MCO' tag that was placed on it in Boston, so I have no clue how in the heck it ended up in Gautemala.
Lesson learned... Never, ever, ever again will I fly with out 'cross packing' all our bags. On our next trip 1/3 of my clothes is going in each bag, and the same for DD and DH! I'll bring 3 swimsuits for each of us, one is going in each bag- same for underwear, tees, shorts, etc! I use packing cubes so I'll just set up a little assembly line. If we end up with a lost bag we will at least have more than the clothing on our backs! Trust me, it stinks shopping for clothes 30 minutes before the Gap outlet closes for the evening, when you would rather be at Wishes!