I don't see it succeeding unless they get Riot Games to exclusively stream on YouTube. That amount of views League of Legends brings to Twitch is crazy.
This would be a good time to be a streamer with a lot of fans to get in a little bidding war between Amazon and Google.
I don't think Google can pay RIOT enough to go exclusive, especially since they need to be able to stream and get revenue from multiple regions, especially China.