1. Droplets: How many people sneeze or cough on others or allow someone else to sneeze or cough on them? Probably not many. IMO, least likely.
2. Surfaces or personal contact: IMO, most likely. Someone sneezes or coughs into their hand, then shakes hands with someone else. Or coughs or sneezes onto a surface that someone else touches, then transfers infection into mucus membranes.
3. As far as I can tell, no one is saying that it is airborne like the measles are. Is this what you are thinking?
But the point is, we know it gets transferred from person to person. How and which method is the most prevalent are probably not known yet.
My brother is head of a small multinational medical company that is in the pipeline. They have been privately working on this since day one. This virus can live in the air several minutes (like measels.) They have determined that all the handwashing in the world won't save you from this if you ingest contaminated air. They investigated cases in-depth where people attended the Houston Livestock Show back in February and didn't eat anything or touch anything. The only thing they did was walk through the arena looking at the animals. They determined the Ro factor of this virus to be about 2.7. Seasonal influenza Ro is about 1. Yeah, it's airborne alright. Big time.