The W/D have mad a huge difference to my packing. I now pack clothes for 2 days (everyone's needs in2 days is different) and do laundry everyday. With a family of 6 it's easy to fill up the washer! On our last the skycap commented on how little luggage we had for a family of 6! I do pack detergent!!!!
I tend to bring along about 4 days worth of clothing for my two DS ages 10 and 7, plus whatever they wear down. DH thinks he needs a different shirt for dinner every night, so he definately overpacks! Plus, whenever my sons get new t-shirts at the parks they insist on wearing them the next day. About the second day into the trip (which is usually 7-8 days) I wind up doing about a load a day, but, as previously mentioned, it's not that bad since you throw it in before leaving for the parks, put it in the dryer before swimming, and it's done before dinner. I guess I'm a laundry freak but I'm already wondering how I'll do on our (first) Land/Sea vacation this October without my washer/dryer I'm used to in our stateroom! I guess we'll really overpack for that one!
We used to way overpack,then we got better and did a load or 2 of laundry(pre DVC), then we packed lots less clothes but lots more food taking up same about of bags(max). Now with the new scanning we will probably be like Nick and Cindy, 1 carry on each and skip the food.
I am so looking forward to carryon trips. It won't be this next one - as the kids are still too young to carry their own carry ons. But by the next trip, it will be a week in four carryons and a laptop case.