There's an interesting blog post at
The Crisper about how Wal-Mart pushed Coca-Cola into offering a sucralose-sweetened version of Diet Coke to replace the aspartame-sweetened version on its shelves. A lot of people suffer minor neurological problems from consumption of aspartame (and some suffer severe problems), but the side effects of sucralose seem to be lower. (And sucralose, aka Splenda, tastes a lot better.) Still, it's probably not a good idea to have artificial sweeteners as mainstays of your diet.