Hi. Here is a link to the photo gallery of the Memphis Zoo: Memphis Zoo - ZooChat You can also look in the United States forum and check under the Memphis Zoo subhead and there is some news and some reviews of the zoo in there.
there are excellent safari parks nearby Drive Through Safari Park, Zoo, Tennessee Safari Park, Alamo, TN Safari Drive Through, Animal Wildlife Park, Zoo | Como MS, Memphis TN
The Memphis Zoo is quite nice and they have added a couple really nice additions since I visited (the hippo exhibit and the grizzly / North America complex). I loved it largely because I am a cat fanatic and they have a nice cat loop, with something like ten species all on a circular path. I flew into Memphis and stayed downtown and took the bus to the zoo, so that is easily doable if you won't have a car. If you have a car then obviously you can get there and the other places mentioned above (which I have never heard of until now).