What do you need permissions for? Unless you were trying to use it internally. I would expect the only use case of Gitter would be to setup a chat room for
github.com/cocos2d-x/cocos2d-x repo, someone with repo access. This creates a single chat room for anyone to discuss cocos2d-x at length. I don't see any need for the community to require more than a single chat room for the public real-time discussions.
If you were looking for a private chat system then I can recommend IRC, Slack, and/or HipChat.
Edit: I probably wouldn't use the chat very often and prefer async discussion, but I would subscribe and there are rare instances where chat is superior to a forum.