Thanks for all your suggestions and ideas guys! I've added a couple more SEO-type modules to my blog (using Drupal).
Actually, I understand your point. But what I am trying to say is that most bloggers are more eager to receive comments rather than to make money. Conversation can make one popular in the long run, and has other advantages as a social blogger. But if you're into Internet marketing, it's better if you can grab the chance to convince your visitor to buy your product - through professional conversation and NOT social conversation.
Ali Hussain wrote a great article on 6 plugins to help you get more comments on your website~ perhaps his ideas listed here can be useful to you There were a couple of plugins that even I hadn't heard about and did help us get in a few more comments
Sweet thanks. Somehow, I got to this page:http://www.turnkeylinux.org/appliances/drupal5 a little while ago. I ended up try all the modules listed there, most of which are pretty useful.