+1. There is the motion detection document, but it's woefully terse. It mentions there is the built-in motion detection, as well as the plugin (or maybe multiple plugins?). But there is no discussion on why one would want to use one over, e.g. features, capabilities, performance considerations, screenshots, etc.
All the Shinobi vs Zoneminder "marketing" fails to credit ZM for its stable and robust motion detection system (at least for me). The performance arguments are valid, and that's why I'm giving Shinobi a try. But I'm already struggling with basic streaming, so am unwilling to spend a lot of time on motion detection until the documentation is current and comprehensive.