non-default subreddits can still be quite good, but many/most/all of the default subreddits are wastelands ravaged by a silent majority of up- and down-voters while the huddled masses of commenters cling together for safety. of course, there's the same phenomenon within the commenters community, where insightful comments are buried amongst puns and prejudice and adolescent jokes that get upvoted much quicker.
I've thought about doing something just like that, but haven't spent the time to figure out a "good" way to set it up.
We had one for our 'post-college' social circle. It was a good way to spread the word about happy hours and parties, without spamming everyone on facebook.