Packing - For Photography

Hi, my name is Will and I'm a cameraholic.  But more seriously, I love photography and taking photos however packing (and carrying) camera gear can be a real pain in the neck (or back).  Decision about what to take, how to pack it, what to pack it in tend to drive me mad but I thought I'd write a bit about my decision process and some cool gear incase it helps you out.

Define some parameters

Where are you going and what will you be shooting?

I'm about to do a bit of an around the world trip which will involve lots of landscape and wildlife photography followed by more city touring.  I would be doing lots of walking both city and trail and will want my camera with me.  [Regions: US, Canada, Southern Africa, Europe, UK]