My father lived in Encino(LA area), in the 50's and 60's and when he last visited (1998)he said he couldn't believe how much cleaner the air had gotten. That says to me that we are gaining very necessary awarness about pollution. I believe that we are on the right track, it's just a matter of time. Unfortunatly the damage that we have done cannot be fixed over night.
I have been to LA once, about 6 years ago. I couldn't believe the smog. I'm not from a big city (just under 200,000 people here) and we live on the plains so all our pollution conveniently blows away, so I'm sheltered. What I remember most is going out to the car in the morning and finding a light dusting - almost like snow - of particulate pollution that had settled out of the air. Much more progress must be made, obviously -- but it's encouraging that there are inroads being made.