I joined Yahoo Groups for their Bernina groups. Can't recommend them. I closed my account and closed my Yahoo account. (Although they keep my information for 18 months! And, not for me to resign up either! They just keep it.) I thought the groups went off topic too often as if they did not have a moderator. When I joined they also were having a problem with a computer virus somehow on one of the groups. They also had a difficult way to handle pictures. They weren't in the post itself you had to go to the quilter's "photo album". Then I found Quilting Board! Yeah! Great people here and we talk about quilting! So there's my word of caution. : ) Good luck!
True, maybe we've outgrown Yahoogroups, but back in the day (not that long ago!) they were the ONLY game in town-- even before Ravelry and blogs! Thank God for them. They were the forerunners of what we have today.