Not only are dialects disappearing, but ever more anglicisms are entering the German language and even change the perception of correct German grammar.
For example one of my pet peeves is:
"Ich erinnere das"
which is incorrect German, because in the German language "erinnern" is a reflexive verb. The correct usage would thus be:
"Ich erinnere mich daran".
Also direkt translations from the English language like:
"Ich bin fein damit", "damit bin ich cool"
are increasingly used (which sound really awful to me).
I don't have a problem with new words entering the language in general, but some of those constructions are really unnecessary and sound very inelegant compared to their original German counterparts.