Thanks, ladies. Botswana is definitely one of the other countries we're considering. Pricewise, I think Tanzania is cheaper and I like the idea of seeing (if not actually hiking) Killimanjaro. I think the trick with either will be to find a reputable tour company that offers the kind of safari that we want, for the right number of days, for a decent price. I'd prefer local or at least one that puts a lot of money back into the local economy and one that is environmentally conscious. About.com has some good suggestions that meet both those criteria.