Thanks all...hope to see some other Kilimanjaro safari shots here too.
Rhinohunter...with that screenname, you sound ready for photo safaris already! (even though the screenname is about the pin hunt). Were you along on the Animal Kingdom photo walk with Tim last year in Pangani Forest? Your avatar is small, but you look familiar, and the Taylorsville NC rings a bell.
Anyway...I love animal and bird photography, and shoot a ton of it here at home...I've had enough practice at it to have gone through alot of trial-and-error to get good results. Even then, shooting from the moving truck takes a bit of luck. My main advice is to use either Shutter Priority, or any shutter-bias setting, your camera may have. Some DSLRs let you choose a minimum shutter speed and a maximum shutter speed, some have a 'sports' scene mode that will do something similar, or when all else fails, choose shutter priority mode and do not go under 1/250 shutter speeds (I'd actually recommend 1/500 or better if possible). If that means you have to raise the ISO a bit, to 400 or 800, it's probably worth it with a DSLR (with most P&S models, ISO400 will likely be about as far as you'd want to push the ISO). As long as you've got the fast shutters, you won't get blurry animals.
The next advice is to shoot multiple frames - continuous or burst mode. Even if your camera is fairly slow, like 2 frames per second, in burst mode, it can still generally fire off photos more quickly than you can. That's what makes digital so great - you can always delete the extra frames you shot when you're reviewing the shots later. I normally don't like to use burst mode on a dedicated wildlife or bird shoot for stationary animals from a fixed position...but if the animal is moving, or I am, then burst becomes very handy. Take the elephant shots I posted - I fired 9 frames, about 3 seconds. 4 of those frames have a tree or bush prominently in front of the lens...2 of them have a pole in the shot from the side of the road...3 of them came out clean, and were usable. All of those things were out of my control...the truck drives along and the trees and bushes intermittently block the view. If you were amazingly lucky, you might have gotten the same 3 shots I did by pressing single shutters each time - but what happens if all three shots were unlucky and had the tree in the way? So use continuous modes if you've got them.
The other advice is to get a 'window' seat on the truck...preferably driver's side (left). Though the right side has a better shot on the savannah area where the giraffes are, the left side gets the best hippo view, elephant view, lion view, rhino view, and cheetah view. Sitting on the left can be key, especially when you're sticking an extended zoom lens out...doing that on a bouncy truck from the middle row won't make you many friends!
I managed to get some decent shots with my P&S cam too on the safari ride...though I was more limited in ISO range, since it got noisy over ISO400. But I used the same basic advice with that camera, and managed some shots I was very happy with. A DSLR makes it a little easier, since you can use a lens better designed for that purpose, you can go to higher ISOs, faster shutter speeds, and faster overall performance, and you can shoot more frames per second than most P&S cams.
If you're going to be at Mousefest, I'll see you on some of Tim's walks and talks. I may miss 101, but should make Epcot and AK...and I'm hoping Tim adds a Maharaja or Pangani animal shoot. If so, just track me down and I'd be glad to stick around and shoot a few animal sample shots with you and give any pointers I can!