One way to have plenty of comments if by award them with the “top commentator”. You can do that using wordpress plugin at http://wordpress.org/extend/plugins/top-commentators-widget/. This will encourage them to post, because top commentator will have backlink to their blog/website.
I have just added the plugin. Test it please. 
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Thanx for your interesting post. But I had difficult time navigating past your web site because I kept getting 502 bad gateway error. Just thought to let you know.
Hmm - It's fine over here - I've checked with proxy, too... Are you still having problem accessing this site?
Any feedback from you?