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Please, this post is 10 years old. If we needed a new post with new and updated links to answer such a simple question, there should be a new post by now. The collection here was compiled back in a time when these were actively used rooms where you can click in to see them actually moving daily, and while that time has passed I don't think there really is a point to removing the links when the name of the rooms by itself already contributes to understanding the environment that was available at the time.
Fun and humor makes up parts of Meta Stack Exchange; I'm not sure how anything else would be on-topic. Several other non-functional chat rooms are sometimes also created on the chat.meta.stackexchange.com domain, such as:
They're not necessarily discussing about the major policies of the Stack Exchange network, but that doesn't make them off-topic. Discussions should be allowed. Otherwise, over half of the rooms are going to die (excluding the Tavern because we cannot live without it):
The faq also says:
Do have fun, but please keep it professional and always be respectful of your fellow community members.
The rooms are not becoming a problem (generating offensive or problematic discussions), so there isn't a need to remove these rooms or discourage discussions. Moreover, the room is also roughly on-topic - Meta Stack Exchange discussions do occur occasionally. For example:
I cannot delete that answer because it's accepted.
yeah, the OP said it's all good didn't you see? That's why I didn't comment any further