Attack of the smog-eating bacteria

Here's an update to "Traffic Jam" from May 1st. It will be submitted as possible cover art, so the blank space at the top is where the title would go. I like this idea better (and more importantly so does the client), but there's something still bothering me about it. I think it has something to do with the photo I took but I'm not sure so I open it up periodically and look at it with fresh eyes.  Maybe it's that I don't want the trees to be green. Hey, it never occurred to me before that I could bring a yearned-for autumn to San Diego with Photoshop. Surprising considering the hordes of pretty people here who have that healthy, just-airbrushed appearance to them.