Sink or Swim with Coke and Diet Coke

We found out that regular Coke sinks and Diet Coke floats! Do you know why?
"The Diet Coke will float because it is less dense than water and the regular coke will sink because it is more dense than water. In regular Coke, more sugar is used as a sweetener also makes it more dense than water and the more dense the substance, it is the more likely to sink. Aspartame and Saccharin are artificial sweeteners found in diet coke. They are at least 200 times sweeter than table sugar. Therefore, a smaller amount of sweetener is used to sweeten the Diet Coke."
Information taken from: http://www.answers.com