Russian language has no dialects.
There also exists, of course, the blatnoy dialect
Blatnoy dialect = criminal slang

if a non-native starts using highly regionalized words in the wrong region and rather inconsistently, he'll probably be laughed at
Yes, exactly so. And if you speak "standard" or "TV" Russian you can be sure nobody is laughing at you. And don't mix Belorussian or Ukrainian language with Russian. They are just different languages, not dialects. Russians often even can't understand Ukrainians or Belorussians. But Belorussians or Ukrainians CAN understand Russians... not because they are dialects, because most Belorussians and Ukrainians SPEAK the Russian language as international in USSR.

The communists had its faults but they did achieve one great thing - nearly 100% literacy among the population of the USSR. Everyone can read and thus speaks the same language.
Not exactly so. Yes, communists did achieve nearly 100% literacy. They taught the people to read and write, but Russians already spoke the same language before communism.

It seems you harbor some fairly disturbing elitism/nationalist-chauvinism/linguistic fascism with reference to "foreign professors" of the language (not to mention colloquial or rough manners of speaking).
I don't think so. It makes a difference between what you (or "foreign professors") think about the Russian language and what native speakers know as native speakers. The sense, not the form. It's very important to see the difference.

Quote Originally Posted by Trzeci_Wymiar
Ty navernoe lobotryas, blya!
J/k. Just testing out my Russian.
It's ridiculous. "Lobotryas" is not "russki mat". It means just a "lazy man who doesn't think about his future". "Blya" is a short form for "blyad'", "blyad'" means "a bitch".