In Moscow there are 2,5 cases of commercial buses: routes that differ from city-owned ones (both local and between parts) and downtown-to-satellite-city_name where there is no other public transport. Both mini and normal buses are being used, as you might guess they are still operating because they fill the niche and are faster than public buses because those have stops each 2-3 minutes. Subway there is far more preferred if it's even remotely an option, due to congestion and reliability.