Guy writes a great piece on the art of building great communities.  Lots of good advice. 

Reminds me of a piece I wrote sometime ago on my experience of building communities at Microsoft (something I've been doing for the last 9 years)   When people ask how I do it, I respond, "Everything I learned about building communities I learnt tending bar". :-)

You can read my complete piece here, but here's the key points:

• A good bartender knows when to be a part of the conversation and when not to.  If someone is alone and has no one to talk then the bar staff will often join in and make them feel at home.  If the crowd is having fun then they should just sit back and keep the bar clean.  That's why sometimes we might be part of the conversation or we might just let one go and create a life of its own.
  
• Sometimes the role of the staff is just to clean up the mess at the end of the day.  On a message board this usually means moving threads to the appropriate forums, deleting spam and fixing broken links in posts.   I compare this to when bartenders make sure that the peanuts on the floor don't start a fire or that there are no health code violations. 
  
• Patrons of a bar are free to choose what conversations they have at their table, they can talk about bars where there might be different music, better food or how much they don't like the atmosphere of the current place.   As long as they are not beligerant to other patrons thats ok.     On Channel 9 we have conversations about competing products, our products and even how we can improve.

Cheers!