With or without a hitch, this isn't quite Twitch.
YouTube Gaming has officially launched today, adding yet another live streaming service to the list of those targeting video game broadcasters (mainly Twitch and hitbox). Official launch information can be found here. Currently the most helpful feature available so far is the option to import channels you are following (subscribed to) on regular YouTube into your YouTube Gaming channels list. The interface may take some time to appreciate, though. (It it just me, or does the 'Channels' sidebar completely block the browser scrollbar?)
The launch of YouTube Gaming also introduces a new live stream interface, replacing the one it was using for the past few years. Scheduling events will soon be a thing of the past with live streams on YouTube. This move is most likely because event scheduling isn't something that other live streaming sites have really used much, if at all. The place to start isn't too hard to find, as it is located at http://youtube.com/stream
A point of interest with the launch involves the live broadcast dashboard and Content ID. YouTube is working with a way to integrate Content ID into live broadcasting and it seems this is a huge decision maker for those questioning a switch. If copyrighted content is detected, the ID system will notify the broadcaster, and will eventually block the stream content until the content is removed. This is different from the detection system used by Twitch, which only mutes audio in previously recorded VOD's when an ID match occurs.
Personal opinion so far? I don't see Twitch missing out anytime soon, but YouTube Gaming is definitely an option worth looking into farther.
EDIT: While it could probably be determined from the official blog post, YouTube Gaming is essentially just an official site/app for finding video game related content on the already existing YouTube site. At least in it's current form, YouTube Gaming is not a new broadcasting service, and the new live streaming interface is a global YouTube launch and not exclusive to the gaming community.