Developer Maxis is currently looking into problems with traffic congestion and pathfinding problems with the streetcar system in SimCity, according to a recent post on the game's official blog by lead gameplay scripter Guillaume Pierre.
Pierre notes that some players have been experiencing problems with traffic "clumping," and streetcars and other vehicles have been taking extended amounts of time to reach certain points. This results in longer waits to complete tasks and in some cases Sims overcrowding public transportation stops. Vehicles all going to the same destination are also currently programmed to follow the same path, which also causes traffic congestion.
Maxis is planning to mark stops crowded with more Sims as "high-priority pick-up" locations, causing transit vehicles to head to those stops first. The developer is also looking into ways to thin out traffic and improve the "clumping" situation caused by current public transit A.I.
For a full breakdown of how streetcar pathfinding works in SimCity, check out the title's developer blog.
Yesterday Maxis launched a status page for SimCity servers, through which players can check the title's server status before logging in.