The company is "sharing all of our brush shaders, our audio reactive code, a streamlined Unity import pipeline" and a few developer-specific features in an effort to get folks crafting wild-looking games, videos and experiences. To give those who are inclined a springboard Google has also included a couple of examples to work from, including a racing game and what UploadVR describes as a "full first-person exploration piece with teleportation."
Perhaps most important here is the integration with the Unity game design toolset. The engine runs on practically every platform and is favored by indie developers -- especially those working within VR -- because of how versatile it is. That it's free for companies making under $100,000 a year is hard to ignore as well.
For an idea of what's possible, peep the video embedded above. Hopefully it won't take long for these animated 3D sketches to show up in more places.