It would not be for interacting, as we already have a venue here. Otherwise, it would be duplicative. (Assuming, of course, Facebook's primary usage is for virtual interaction. Since I do not visit Facebook, I may be mistaken.)
If Facebook can help in new member acquisition, then it might be something worth considering. This assumes that a broader membership base may lead to reaching critical mass more easily on many of the Cloth Club projects, as well as increasing the number of (quality) contributions in the LL Forum. That said, I have no idea whether Facebook is the right medium for achieving these objectives, assuming that they are indeed objectives.
I must admit to being one of the old farts who have absolutely no idea about social media, so I am just rambling here...

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