Museums on Facebook — making friends, making fans or simply broadcasting?

Many museums struggle with how to integrate Facebook (and other social media) in their collections, exhibitions and physical venues.
Therefore it was interesting to read Benjamin Thompson’s report from a Eureka Live event, ‘Facebook: bad for friendship?’, held at the Wellcome Collection in London, some time ago.
One of the discussion topics was whether you can have too many friends on FB. Spreading yourself ‘too thin’ means you can’t invest as much time into each ‘friend’.
Agree! And, by the way, what does the word ‘friend’ really mean? Frankly I just hate the word ‘friend’ in this context. Facebook is actually more an ‘acquaintancebook’ than a ‘friendbook’. And when people have more than 150-200 ‘friends’ (Dunbar’s number), these aren’t even ‘acquaintances’ anymore, they’re reduced to fans. In fact, institutions, including museums, mainly use FB as a broadcasting platform.
Accordingly, there seems to be a trend that people are purging their Facebook accounts, leaving only close real friends and family, using Twitter instead for the broadcasting of their thoughts. Maybe that’s why our museum recently has put more emphasis on being present on Twitter?
So whereas Facebook is about branding and broadcasting under the disguise of ‘friend-making’, Twitter is a least honest — it’s openly broadcasting, period.