Beverage dialect(ic)s

The blogosphere indeed has its virtual finger on the pulse of the national zeitgeist. Why, just the other day some of my colleagues and I were discussing how they generically referred to soft drinks or carbonated beverages; being Kansans, they almost universally call it "pop." I, on the other hand, was looked at rather strangely because I had grown up calling it "soda water" or "coke." And today, via Matthew Yglesias' blog, this intriguing map on this very subject that shows our nation to be a much more diverse place than all that so-five-minutes-ago red state/blue state rhetoric would have us believe. Mr. Yglesias goes on in his post to compare and contrast this data to voting patterns in the national election, but I'll head in another direction.
What's intriguing to me is the "other" category. You'll be delighted to know that popvssoda.com also keeps track of those responses, so I visited the stats for Texas. As you'll see, "soda water" and its variants, if they were lumped together into the same category, would form a sizeable minority, though still overwhelmed by "coke" speakers. I suspect that that number will decline over time, though, as residents from the West and Midwest continue to move there. My sense is that "soda water" was fairly archaic even when I was growing up in the '60s. I grew up in a rural area west of Austin that was not very southern in its culture--we looked West, more often than not; I thought of East Texans as exotic, not as brethern.
It is strange how regional vocabulary marks one. I have lived in Wichita for 4 1/2 years now; I hear people, including Mrs. Meridian, call it "pop" every day; but it still sounds alien to me. So also do other Kansas verbal tics such as using "anymore" in the sense of "nowadays," and adding an extra "s" to any plural possessive ("boys'" is pronounced "boyzes" here). I'm sure that somewhere in all this is a comparison to be made between the language habits one learns and genetic coding . . .