Ammonia oxidizing bacteria can thrive in livestock buildings... In fact they are being used in ‘bioscrubers’ in livestock buildings where they are encouraged to multiply within the scrubber to remove ammonia from polluted air before existing the building by coverting ammonia into nitrate. (http://www.agronext.iastate.edu/ampat/animalhousing/scrubber/homepage.html)

Yes..some of organism thrive on enhanced gases (otherwise air pollution)

Well, I think is difficult to do hypothesis for this question because air is dynamic and bacteria in atmosphere is difficult to be control. May be can investigate some species of bacteria in dust in door and could have relationship with some pollution degradation. 

As the question is very broad, among possible answers are.. Yes, some researchers, as this will provide them with more funds, also Doctors, Pharmacists and Undertakers.  

If you look at the main air pollutants emitted into the atmosphere are; 1. Carbon dioxide 2. Sulfur oxides 3. Nitrogen oxides 4. Carbon monoxide 5. Volatile organic compounds; they are categorized as either methane or non-methane (NMVOCs) 6. Toxic material lead and mercury and their compounds 7. Chlorofluorocarbons ( CFCs) 8. Ammonia. There are organisms who can benefited due to high concentration of sulfur oxides, nitrogen oxides, ammonia and methane in the air so far my knowledge goes. But definitely it is an interesting topic and more research is needed on the subject.

Prof. Towe, I have only given a list which can be consider as air pollutant ( not first or last). To define exactly, Air Pollution refers to any unwanted or undesirable change in the physical, chemical  and biological properties of air. The Environment Protection Agency's decision is classifying rising carbon-dioxide emissions as a hazard to human health. Actually increasing concentration of CO2 is to concern to the agency. 

Yes there are many such as phytoplanktons and cinobacteria.