Second, there's no easy way to get a custom URL for your broadcast channel. What I had to do is use a Google+ page that had the same name as my personal blog, then I created a YouTube channel for that Google+ page, then I got a custom URL for that channel (they call it a 'custom' URL but Google generates it for you based on your name), and finally I copied my old channel to this new channel. Whew!
I think you could skip the Google+ bit and head to https://www.youtube.com/account then click on "See all my channels or create a new channel" and add a new channel that way, using as a name what you want your custom URL to be, and hoping for the best. (You can probably tell I wasn't taking notes during this process and was just trying different things until I got the results I wanted.) Anyway, it's clear that Google needs to offer an easier way to set up a custom URL to share with friends.
Third, I've heard some broadcasters express concern that there is no real way to monetize their content. On Twitch they can set up a Subscription to directly generate income from their viewers, but YouTube Gaming doesn't have a similar system.
And finally, they need to update apps on the game consoles. Lots of people broadcast to Twitch from the Xbox One and the Playstation 4. If YouTube wants to compete with Twitch it needs to give console gamers the tools to broadcast to YouTube. As well, they need YouTube Gaming apps on the consoles to supplement the existing YouTube apps.
So there's work to be done but again, I think they're off to a good start. Some of the broadcasts I've checked out have been really sharp; it might just be that 'new service smell' but it seems like YouTube Gaming is capable of delivering higher quality broadcasts than Twitch can. Don't take that as fact, it's just my subjective opinion based on watching a few streams. Definitely take a look and make up your own mind.
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