Well I wanted to register and use it, but registration was closed. I've subscribed to be notified when the registration will be open again, but notification never came. Later I forgot about it completely.
In the meantime I listened to a few interesting current-events discussions on Twitter Spaces, but only by coincidence that I happened to see them as I was browsing right after work. I don't see how anyone can build a business on only this type of content, it's too synchronous.