Many thanks for affirming the value of this facility, and those who use it. It is a perfect solution for folk who have met on the forum and who wish to discuss things beyond the remit of the forum, or who wish to open up about themselves in a smaller group.
I can only give my own experience, but I visit the site much more often because of the group conversations than I would for just the forum topics alone. Perhaps a higher profile of this facility will increase the site hit rate.
There are a couple of other issues that have arisen with this change. On the conversations, the other posts are blacked out while trying to reply. This means you can't read what you are responding to. The disappearance of the spell checker has been noted. Also the location of each member is no longer automatically displayed against their post. (although I note that some people have worked out how to do it). It is sometimes essential to know where someone is located in the world to tailor the response to a question.