Since we will be traveling by foot, train, plane, car, and bus, we are going to pack lightly. (Not to mention that the airlines now charge an arm and a leg for each bag you take.)
I have a Go-lite backpack. It is an "internal frame" backpack, however it does not really have a frame. It is the most comfortable and strong backpack I have. It is also pretty roomy.
As for shoes, I plan on taking a pair of Keen sandals and a pair of leather flats. The sandals can double as hiking books for light hiking, and the flats can go with dresses, and are closed toe for touring churches where open toes shoes are not allowed.
I plan on 3 pairs of pants: jeans, shorts, and a pair on long black (polyester) slacks. I want to take 7 shirts, but we will see how much room they take. In China you can buy disposable underwear, but I never saw anything like than in Europe, so I guess I'll have to bring handwashable underwear. I am bringing one dress and a bathingsuit.
Now the fun stuff: camera, check. iPod, check. international adapter, check. Phone with international card, check. Other fun stuff: notebook and pen.
Essentials: sleep sheet, limited toiletries, medication, ATM card and credit card, identification and passport, and itinerary. Oh, and cash.
I need to remember to tell the boys to make sure they xerox a copy of their passports and flight information and leave the copies with loved ones, just in case someone looses something. I have traveled alone abroad before, but these two boys are greenhorns.