Phil Harrison, vice president and GM of Google Stadia:
Using our globally connected network of Google data centers, Stadia will free players from the limitations of traditional consoles and PCs.
When players use Stadia, they’ll be able to access their games at all times, and on virtually any screen. And developers will have access to nearly unlimited resources to create the games they’ve always dreamed of. It’s a powerful hardware stack combining server class GPU, CPU, memory and storage, and with the power of Google’s data center infrastructure, Stadia can evolve as quickly as the imagination of game creators.
They have a custom game controller too, which from the outside looks a lot like a Sony Dualshock. The innovation is that the controller isn’t a peripheral to a local device — it connects by Wi-Fi to the Stadia cloud.
Streaming high-performance games over the internet sounds like something that could never compete with a local device, but no less an authority than John Carmack vouches for it in principle.
It’s worth pointing out too that this is a very Google-like strategy, where your device doesn’t really matter, only the cloud service.