Two in the top 5! Woohoo!
Book clubs in general (real life or other online ones) are hard to maintain momentum for a bunch of reasons (attention, timing, etc). I think the fact that both SN and ~BooksAndArticles are still growing and developing doesn't help (we don't have the network effect of a 10000-member subreddit, for example).
You're alreqdy a territory all star! Good point re SN. Perhaps these issues will dissipate as the site grows.
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