One trend that is rapidly occuring is the change in regional accents or their disappearence. The question is, are accents merging into one, or are they simply evolving. While it is not that important, if soceity loses regionalization and becomes one giant blur then people will be easily controlled. As for dialects, expressions spread. In the 1970's, Soda was strictly a New York term. Now it has replaced the term" tonic" in the New England dialect. It is meaningless, but could be a sign of regions submitting to big cities.