I don't think there'll be too many changes to groups. People still have to willingly join a group, and it already bases group notifications on how much you engage in the group (if you comment/reply a lot, you'll see more notifications in your feed for that group)
I actually think the recent announcement of changes to Facebook was a huge non-announcement. They basically just said they'll be doing what they announced back in 2012, or whenever it was that they did the last major algorithm change.
Fair point. It might really end up as, more of the same :)