Writing most of your front/backend business logic in Go is one possibility, but I think that easily moving complex logic to the web as a platform (especially for web demos, see these[0] example with gopherjs) is the most compelling possibility. Generally, I'm excited that this democratizes the web programming space, because the best use cases are often the ones no one has thought of yet.

[0]: https://hajimehoshi.github.io/ebiten/

Even just boring stuff like being able to have one object definition somewhere shared between client and server is useful.