According to Coke lore, Coke had created 'New Coke' and then changed back to 'Classic Coke' because they altered the formula from cane sugar to corn syrup, and when they brought it back on the market, people didn't notice because they were so happy getting the old flavor back.
If you were to sample a 'normal' Dr. Pepper with one from <a href="
http://www.dublindrpepper.com" target="_blank">Dublin Dr. Pepper</a> you could tell the difference in corn syrup and a cane sugar cola, as the Dublin plant is the last DP plant to use cane sugar. Delishious!