Definately one of the nicest things to do in the Selous is go for an evening boat trip. Sometimes animals can be a bit scarce, but you see plenty of hippos and crocs and HUNDREDS of birds. I was never really interested in birds until I started paying attention to the birds in the Selous. Look out for Boehm's Bee-eaters, all kinds of kingfishers and (my favourite) the African Skimmer. Most of the camps in and outside the Selous operate boat trips.
Lions, hypos and the rest of the gang
Well, no much point incoming all the way here without going out to the bush. See the travelogue section for some pictures.