It's seriously fucked up. I've spent a dozen hours and a million sim-dollars trying to fix traffic in my city. To the point where I have a greater number of people riding streetcars than it says are in the city. I have a population of 58,000. Under the transit tab it says 64,00 are riding my streetcars. And the worst part is, traffic still fucking blows. It barely changed. So when the game says to beef up transit in order to reduce traffic, punch the game in the face for me.

Oh, and the way you increase transit users? Put a bus stop/streetcar stop every 2 feet. more stops = more passengers.

If you have residential areas closer to industry/shops the people living nearby will walk to those destinations instead of taking their car. That's one way to help the situation at least.

But residential next to industrial is bad, isn't it? especially with all that pollution.

buses fix everything

I punched the game in the face for you, I think that did the trick.

Many aspects of this game is bad in some way, but good in other ways.

Stores as well as factories have scripted behavior in that when they need new workers, they search for unemployed citizens in a close radius and gradually expand that search radius until they have found workers for their vacant positions.

Yes, factories, depending on your tech level bring you different levels of crime and pollution. Stores bring you crime, but not that much pollution. You have to decide what is most important to you. If you have a city with schools and a high tech, your pollution/crime hit won't be as large and you should probably consider weaving in more residential zones closer to your workplaces, commercial zones especially, but factories and such too. Every person you see walking around in the streets is good, because they're not driving a car. Each grown-up citizen can summon their own car, and you can imagine the amount of traffic that can inflict on your network of roads.

If the roads are clogged: Your citizens can't get to work. That means citizens employed in your services, such as police, bus drivers etc, can't get to work and your services will take a hit in performance. Your school buses won't pick up your students so they will have to walk far or perhaps they will quit school.

A high density roads will let you cope with more traffic, but even those can get clogged, so be sure to have plenty of buses (and bus stops!) too.

I'm sure there's a lot more to this, but yeah, it is worth it to experiment and learn the implications/pros and cons of the various strategies you can employ to solve the traffic issue. The roads are the veins of your city so yeah, its not good if they're not flowing somewhat freely.

@bombedyermom: It's possible that you have a large number of visitors from other cities which would explain the number of people using mass transit but traffic still being crazy. There is a pie chart for visitors vs residents somewhere. Also, be careful about having too many stops. The more often your buses stop, the more often everyone behind them stops too.

Don't feel too bad though, the AI for vehicles just seems wack overall.