A highly placed source just confirmed for me that one of the major manufacturers is working on a hybrid system combining both dirt and spit. They are claiming a huge increase in dynamic range, with nuanced shadows in the dirt and airy highlights in the spit. The major drawback of the system is that they haven't figured out a way to keep the lenses completely free of dirt and spit, thus limiting resolution. However, they are close to solving the problem with a proprietary automatic lens cleaning system code named "Windex", which will be available as an option for professionals/advanced amateurs seeking the very highest resolution captures.