Years ago, Google purchased Sketchup as part of a plan to have everyone around the World model their local environment, upload this to a global free database/resource and make this available via Google Earth or other means. In practice, this never really happened and SketchUp became a tool that became increasingly used for rapid modelling of built environments.
When Google decided that SketchUp wasn't part of their grand plans, it was sold to Trimble. The development team also moved to Trimble. The focus of development is now on the professional application of SketchUp. SketchUp Free should continue to be available but SketchUp Pro is set to receive the development it's lacked for several years.