IMO, even the blogs have a tag of “nofollow”, we can still benefit from commenting on their blogs.

Glad to see Brandon here, too. IdoBlogs also is a good blog providing useful inforamtion for bloggers.

“There’s no such thing as a “duplicate content penalty.” At least, not in the way most people mean when they say that.”

With that being said they also note that such a penalty does exist but only under certain sitations. An example that would get you penalised for duplicate content is as follows.

- If you are caught leaching or scraping information from other sites and republish it without adding any additional value to the information.

- Don’t create multiple pages.. subdomains.. or domains with substantially duplicate content.

- Avoid… “cookie cutter” approaches such as affiliate programs with little or no original content.

- If your site participates in an affiliate program make sure that your site adds value. Provide unique and relevant content that gives users a reason to visit your site first.

“Duplicate content on a site is not grounds for action on that site unless it appears that the intent of the duplicate content is to be deceptive and manipulate search engine results. If your site suffers from duplicate content issues, and you don’t follow the advice listed above, we do a good job of choosing a version of the content to show in our search results.”

You can read more about it @ http://www.domainstructure.com/2008/09/duplicate-content-penalty/

and also @ http://googlewebmastercentral.blogspot.com/2008/09/demystifying-duplicate-content-penalty.html

Still think though that the big money is in the, unfortunately, highly competitive keywords