>>386562080
>I haven't followed it much
Right, well the quick rundown: 

Supports PC fully (now that we know), is much lighter, smaller, and more comfortable because it uses pancake lenses, the lenses are much clearer and displays are slightly higher resolution of 2.16k per eye, HDR, has face and eye tracking, has support for wireless if you want it, and has more ergonomic controllers that are self-tracking so no occlusion problems like Lighthouse, but better since it can operate without base stations. Also has higher quality and depth correct color passthrough, and has markerless hand tracking like Leap Motion if devs ever support it. 

Cons are that it doesn't have the excellent ear speakers of Index and it's not natively integrated with Lighthouse, so setup with FBT will be more janky.