What significant impact did Mikhail Gorbachev have on Russia?

His impact was to present the image of a more-open Soviet Russia to entice increased Western trade while preserving the core of the Soviet Union.

He also betrayed the people of his country. He was a weak and mercenary leader actually and everyone hates him for that. Now he lives in London (afraid of retaliation) and makes money from food called in honor with him: Pizza, vodka "Gorbachevka" and so on.