Alan McConchie has created the Pop vs. Soda page, an Internet database that maps the regional differences in how Americans refer to soft drinks.
Looking at the large number of people in the south who call all sodas "coke," regardless of brand, doesn't that suggest one of the world's most lucrative trademarks has become a generic term and should lose its protected status?
Aspirin, cellophane, escalator, nylon, and thermos all were once trademarks lost by their companies through generic use.
On BusinessPundit, a southern cokehead named Alan Ruff writes:
... when I first moved to Iowa from North Carolina, people looked at me with the weirdest face when I would say, "I'll have a Coke, make it a Dr. Pepper."