Ah, what a grand day, indeed. We present, Solgaleo and Lunala, the two newest legendaries in the Pokémon universe. Solgaleo (as seen on left in picture above) will star in Pokémon Sun, and Lunala (right) in Pokémon Moon. Both look like they could deal out a massive whooping on lil Popplio. Here's the new trailer which features the legendaries, as well as new gameplay footage, and a look at the new Pokédex:
In Sun and Moon all players will get a Pokédex inhabited by the ghost-like Pokémon Rotom, who can possess/inhabit objects and machinery.
The Pokémon company said the following about the exciting new Rotom-Pokédex:
“It does much more than record Pokémon info—it sparkles with its own personality. The Rotom Pokédex shows your current location and your next destination, and it also gives you advice on where to go next, based on the conversations you have with others! It’s likely to be of great help to you in many parts of your adventure.”
Lastly, here's a detailed look at Aloha: the Hawaii-inspired region of Sun and Moon: