Get a group of kids from all over the United States together, give them some soft drinks, and pretty soon you'll most likely hear an argument about what they are drinking is supposed to be called. Minnesotans and Oregonians will probably call it "pop", most Texans will call it "coke" - even if it's a 7up - and Californians and New Yorkers will call it "soda". In 2003, Matthew Campbell and Prof. Greg Plumb of Oklahoma's East Central University conducted a survey and made this detailed map which breaks it down county by county across the nation:
While this map is now six years old, others have now taken up the task of charting the great American soda pop divide. This site has a much more recent map which nicely demonstrates that our language is constantly moving and shifting. According to the first 715 respondents, it looks like "coke" has made considerable advances into the Pacific Northwest while "soda" is spreading further into the Great Plains states. What do these shifts signify? So far, there are no major theories, but these kinds of linguistic changes are often tied to cultural change. This is best illustrated by looking at another common foodstuff that similarly divides the nation.
Submarine sandwiches are famous for the variety of names they go by - hoagies, grinders, heros, and more. This wikipedia article not only has a nearly complete list, but also explains some of the historybehind the different names. The sandwich itself originated in Italy and was brought to the US by immigrants in the northeastern US in the late 19th century. Different names for it emerged in different cities - the term "hoagie" for instance originated in Philadelphia while "hero" came from New York. The spread of "hoagie" from workers on Hog Island in Philadelphia, across the state to Pittsburgh in the 60's reflects the spreading influence of Italian-American culture. More recently, a newspaper in Vermont proposed that the state invent a new, unique name for the sandwich, reflecting that state's own unique culture.
If you've noticed new names for everyday items in your area it could signify social change. As cultural values change, globalization increases, and various areas of the country experience demographic shifts, parts of our everyday vocabulary change as well.