When using keyword search
When the map view loads, the initial zoom level is set to show all listings.
For example, if your marketplace only contains listings in a small area, the default zoom will show that area. But if your marketplace has listings from all around the continent, the zoom will be set to show the whole continent.
When using location search
When the map view loads, the initial zoom level is set to automatically show the correct searched area. The search knows whether you tried to search for a street name or a city, and adjusts the map zoom level correctly.