In theory, would it be possible to make a modified !gnusocial with an emphasis on groups, with a reddit-like interface? Essentially the groups would operate as subreddits, and threaded conversations as comment threads.

It's mostly a shower thought, and I'm not familiar enough with the protocol to know how you'd do things like up/downvotes, but the idea of a federated reddit clone (with GS interop) seems interesting.