I've identified two suitable themes, both of which I feel are very friendly towards the 'community' feel that we are trying to maintain. Both are by the same author and somewhat similar however the content areas are very functional. The headers leave something to be desired but if we are only looking for content layout then that should not be a problem.
Open -
http://open.themedemo.net/ - I personally use this one.
Collective -
http://collective.themedemo.net/
Something important that can not and must not be overlooked in selecting a design is the layout of the comments area. In order to have readers actively engaging they need to be comfortable browsing through comments and be easily able to add their own. This is an area often overlooked by designers but is arguably more important than the body of the content.
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