The announcement on the YouTube Creator Blog didn't mention a specific launch date. However, the details show a service that is similar to other live platforms, with the ability to allow live chat, make the stream public, and notify subscribers.
Google also proclaimed it would have an inherent superiority with its take on livestreaming thanks to its longstanding ability to host most of the world’s online videos. The live broadcast feature is coming first to YouTube’s more popular creators before it’s made available to all, presumably to work out any issues before the masses can partake.
Why this matters: Live video has become very popular, most dramatically this week when U.S. House Democrats used Periscope to live broadcast their sit-in to call for a vote on gun safety legislation. With this capability entering the mainstream, YouTube certainly doesn’t want to be left out while rivals Facebook and Periscope take up all the attention.