It looks interesting, I wonder if these type of projects will eventually replace IRC. I could definitely see popular open source projects using this over IRC, especially if they have features like snippet embedding.
Yes, Leafy Chat was a totally separate project built by myself, Alex Gaynor, and Chris Wanstrath for the Django Dash a couple years ago. Leafy Chat was a pure web IRC client. Convore is inspired by IRC but not based on the protocol and functions a bit differently. For example, Convore has the concept of topics, which is not in IRC.
To be fair, IRC has the concept of topic, but it's per channel. Channels can't have multiple official topics, but, as we all know can definitely have multiple off-topic conversations.
I've been using convore and thinking about it in terms of asynchronous IRC with sub-channels. (i.e. each group is a channel, and each topic is a sub-channel composed of the same channel members, with a different topic.)