I also highly recommend the new Canon image-stabilization lenses.
This technology has been applied to most of the Canon long lenses,
and it gives about three extra f-stops before camera shake becomes a
problem. I recently took three of these image-stabilized lenses to
Antarctica; the results were so good that, if I was able to go again,
I would not bother taking a tripod. The forest environments here are
much darker than the wide open landscapes of Antarctica, but a
combination of an image-stabilized lens and fast film--pushed even
faster if necessary--should cover many situations.

Lee Rentz
lee at leerentz.com
Shelton WA 98584