Here is the official word from Ted Price (Founder of Insomniac):

"Today we’re announcing Song of the Deep – a brand-new Metroidvania-style underwater adventure. In the game, you follow Merryn, a young girl who is trying to find her father – a fisherman lost to the depths. She builds a rickety submarine to search for him beneath the waves.
You can check out the debut trailer for the game here:
You’ll follow Merryn’s submarine on a journey under the sea, exploring an expansive and mysterious world. You’ll discover sunken cities and diabolical puzzles. You’ll upgrade your ship with new abilities powered by a mysterious substance called Tyne. You’ll battle strange creatures who are intent on dragging you further into the depths.
We’ve been secretly working on building this strange and beautiful world and are now excited to share the first glimpse with you!SOTD_MerrowRuins_Statues SOTD_SeaGarden
We’re also happy to say that the game will be available on PlayStation 4, Xbox One, and PC. No matter which platform you prefer, you’ll be able to purchase the game physically atGameStop stores (you can pre-order it from them now) or you can download it directly from PSN, Xbox Live, or Steam. Song of the Deep launches in Summer 2016 for $14.99.
We’re looking forward to sharing much more from Song of the Deep in the months leading up to launch. In the meantime, you can follow Song of the Deep on Twitter, Like it on Facebook, or discuss in the forums!
Thanks for all of your support of Insomniac and our games!
Ted"
The crazy thing about this is the the game is being published by Gamestop. In turn you'll only be able to grab the physical copy from that retailer. It's happening people, Gamestop is further trying to ruin the sanctity of the game purchase formula. Mark my words, we will soon see games made with a playable Gamestop logo like they did with McDonalds and Pizza Hut in the past!!