A year ago at this time I was toting a basic Canon outfit, a 5D, a 20D, two zooms, and a 50mm macro around Israel and Jordan. Never again!
Trudging through Petra, the amazing city carved into stone cliffs, cursing with every step my increasingly heavy camera bag, I chanced to meet a German who was carrying nothing but an Olympus Pen E-P2 with the 14-42mm kit zoom. We talked for a few minutes, and I asked if I could hold and look through his camera. That did it for me.
From now on, my travel kit will be a pair of E-PL1s with a VF-2 viewfinder, a 12-60 zoom, and a Panasonic 20mm f1.7 in the lightest bag I can find.
My experience is that the more equipment you carry, the worse your photography is likely to be.
And absolutely do not try to mix film and digital on a trip like this. The photographer who tries to cover all the bases winds up covering none of them to his own satisfaction.