The reason people don't like diet soda - is not so much the taste, but rather the "mouth-feel".
Researchers have discovered that people can accurately discern the difference between beverages made with sugar and those without - all based around the texture. Drinks tested included Pepsi, Diet Pepsi, Pepsi Edge, Coke, Diet Coke, C2, and many more.
The panelists became so skilled that they were able to accurately identify significant differences in the mouth-feel of 14 samples that sensitive lab instruments identified as very small. (via Livescience)
It seems that we are good at picking out beverages with High-fructose Corn Syrup - and we prefer the texture of these to artificially sweetened beverages.
Food scientists will be scrambling to find an additive that has zero calories but has the same texture as sugar.
"If we could make diet soda taste better, it would be a big step in fighting the obesity epidemic," Schmidt said. "Many people know they should cut calories, but they won't drink diet pop because they don't like the taste."
Forget the "obesity epidemic" - more like a big step in selling more cans. There is no evidence (as far as I know) that links diet soda consumption with lower weight (if anything there is an inverse correlation).