joelandsonja: I was wondering the same thing myself, but I hope it's not a stream from PC service, because I doubt there are many people who would be willing to give up their own Internet bandwidth to a video streaming service.
Depends. After all, people are willing to give up their internet bandwidth also on bittorrent, emule etc. so that others may download stuff. Even my mobile phone's car navigation software has the option to use peer-to-peer technology to download navigation maps to the device, ie. as you are downloading them from other users, you are also uploading them to others.
It doesn't necessarily mean that thousands of people need to be specifically sharing some video day in day out, but e.g. it already helps a lot if people, who are watching some streamed video, are at the same time streaming it to others. The more there are watchers for some video, the more there are also people sharing it.
Anyway I don't know if that is what LBRY is about, but I feel it would be the only way it could compete with Youtube, by not being a youtube clone but a decentralized video streaming protocol. The failed Vimeos and whatevers are an example of losing the battle if you try to be just like Youtube.