During their E3 Spotlight 2017, Nintendo presented a very small teaser for Metroid Prime 4. It was announced to be in development for Nintendo Switch, although not much more is known regarding this reveal.
What is worth talking about, is the style of the announcement. Following on from the Pokémon company discussing their new game, the screen faded to black, before a nebulous Screw Attack symbol appeared in space. A large black floor 4 then appeared on screen. After a pause, there was movement across and the reveal that most hard core Nintendo fans were waiting for: Metroid Prime 4.