Trzeci_Wymiar, you are repeating some definitions of the dialect over and over again, but it's a pure casuistry, really. Yes, we know (and happily agree), that slang exists in Russian, yes, we know that some dictionaries and linguists regard slang as a dialect, but it's not what this discussion is about, and you know that!

The topic starter asked about the existence of the appreciable regional differences in Russian language, similar to multiple regional dialects in English, and there is no such thing. While there are some divergences, Russian is still remarkably uniform.

So that's it.