So what is Daydream? Daydream is, in essence, a specification for a headset and input device together with a number of requirements device manufacturers need to follow to have their devices Daydream certified. Being Daydream certified means the device is capable of providing a great VR experience similar to what Oculus GearVR offers.
Daydream also comes with functions built into the upcoming version of Android such as providing users with a virtual hub where they can launch their apps and games.
More information about Daydream can be found here: https://vr.google.com/daydream/
So why is Daydream and it's presence at Google IO a big deal? When a company of Google's magnitude show this kind of comittment to VR it's a fantastic recognition of the platform itself but it also shows how important VR is for Google. This sends signals to the developer community which helps developers embrace development of VR content and grow the VR market.
In a not very distant future, millions of people will have Daydream certified phones, which together with a cheap headset provides a complete VR setup.
It's not a wild guess that Daydream will be the stepping stone for many users who will have their first VR encounter with a Daydream certified phone.
We have already seen proof of this with GearVR. 6 months post launch and GearVR already have 1 million users according to Oculus. With Daydream coming the mobile VR market will grow rapidly.
Even though mobile VR can't compete with Desktop VR in terms of visual fidelity, the vast majority of users will find mobile VR experiences good enough just as they already do with gaming and apps today.
But what sets mobile VR apart from ordinary mobile games is that the immersion mobile VR provides is almost as good as what you get from PC/Console VR, whereas most mobile games today are quite different from PC/Console games.
So Daydream is a big deal because it will help drive adoption of VR regardless of platform. And this is awesome!
