We flew cross country twice since "the london plot" was uncovered and had no problems. Just carry on the minimum and pack everything else. There has always been a chance of lost luggage but because more people are checking more bags now it has increased. You just can't worry too much about it. We put one change of clothes in our carry on and a sweater/sweatshirt plus snacks but no drinks.
Use common sense ideas: do not check your valuables, laptop, jewelry, camera or anything else you can not bear to be without for a day. Don't wear gel insoles-lol-true we saw people having to remove them. Don't try to carry a drink on the flight. You can still carry food on board though and the airlines still give you drinks. Make sure you put some ID INSIDE your luggage stating your itinery with dates-you don't want them sending your luggage home if you are in DL. Put your hotel and dates and phone number on a slip inside your suitcase right on top, easy to find.
Pack with security in mind, make it easy for them to see everything they need to see and put back in and close up easily. Don't break the rules by trying to sneak a lighter in your checked bag for example. Pack all of your liquids in gallon sized ziplock clear baggies. They won't leak and can be easily inspected. Tell your wife to get a cheap tupperware type of see through container for her makeup. I think they are made by Glad and you get them in the grocery store. It works great and keeps it all together, no leaks and they will not even have to open it.
Then finally, pack only clothes in one case( if taking 2, put some of each of your clothes in each case). Don't pack one suitcase all his and one all hers, mix it up and if one is lost, you will both have something to wear. Pack the "hard" stuff in another suitcase like shoes, hairdryer, curling iron, make-up, & toiletries watching your weights cause they are only 50 lbs. now, not the 70 it used to be. When they inspect each piece, they really will only have to look carefully at the one bag with the hard stuff instead of each case. They always have to look at the curling iron-lol-so put it on top! Each time, every single piece of our checked luggage was opened and swiped with the explosive detecting pads in front of us. Don't over pack any one bag, make sure they are easy to close again by security! We've seen them get angry when they opened someone's suitcase and all the stuff fell out. It seemed like they took twice as long after that to finish screening the bags.
Get there early! Arriving late is one major cause of lost luggage as is not using proper luggage tags. When you check in and they put the sticker on your luggage, WATCH and make sure it says which airport you are going to! Make sure they tag each bag! Speak up if you can't see to double check. Stand there until you see each piece get put on the belt at check in. We saw lots of people walk away and their luggage never got put on the belt. The check-in guy kept asking us if the carseat sitting there was ours and I just knew then that family lost their carseat simply because they did not watch and make sure it got put with the luggage. There was no name on the carseat either-that's just stupid!
You will be fine and figure someone you know has already recently lost their luggage so the odds are slim for you and your wife. Don't accidently pack your watch, they will steal it and then your luggage will be delayed to cover up the theft-lol. Just be smart, pack smart and you will be fine.
We shipped stuff home simply because we bought too much stuff on our trip to pack. IT was almost $100! and did not come when they said it would, came 4 days LATER! Not a big deal for us but had we needed the stuff on our trip, we would not have been happy.
. Her sister's luggage was lost this last weekend on her trip to visit us. It did arrive the next day late, but still prompted an expensive trip to the store for all neccessities. We are flying United into LAX and she is worried about the airline losing our luggage on the way out. 
and what if they don't carry her specific kinds 
?
