I guess the title says it all. I am taking a trip abroad and need a good soft case that I can take ON the plane with me. Not just US commercial, but smaller, local airlines as well. Then I'll have to carry it around with me. I've got it narrowed down to the Petrol PCCB-2n or the Lowepro PhotoTrekkerII backpack. Any suggestions, advice, other reccomendations? I don't want to carry around anything too huge, obviously. This is a one man show. Thanks!

I'm happy with the Tamrac 2249 soft case:
http://www.tamrac.com/2249.htm

It fits my XL2 and accessories well (it was made for the XL1). I can't say anything bad about it for the money (about $200). It fits the camera fully ready to run-and-gun. In fact, the camera can be easily removed from the bag to shoot immediately without taking the bag off of your shoulder, so you don't have to leave it somewhere or let it get dirty on the ground.

It's small emough to be an overhead carry-on.