スペイン宗教裁判式バージョニング

バージョン番号の指定方法と意味合いが変わってて、こんな感じになってるみたい。

You can indicate which version of the API to load within your application by specifying it using the v parameter of the Maps Javascript API bootstrap request. Two options are currently supported:
・The release version, specified with v=3, or by omitting the v parameter.
・The experimental version, specified with v=3.exp.
・A numbered version, indicated with v=3.number, which specifies a feature set of the API.

https://developers.google.com/maps/documentation/javascript/basics#Versioning