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If you want to avoid the duplicate content issue, you must use original content on the page. Each product needs a unique description. Any duplicate content caused by a product having slight variations like size or color should be resolved by placing rel-canonical statements on the duplicate pages to tell the search engines which is the official product page. There is no way around writing original and unique product descriptions. If your client does not provide them or pay you to write them, then you must have a firm conversation about the problems and likely results...or lack of results.

Yes, Ben, I have seen this and it was very pronounced on one of the websites I support. Rankings for Google remained, shifting a little bit due to some technical and content SEO changes. The shifting in Google was desired. However Bing/Yahoo dropped all keyword rankings that we are following. From many to zero in one week. And, the sitemap in Bing Webmaster Tools has been pending for 2 weeks now. Although concerned, I figured this was a response to the elimination of duplicate content from technical SEO changes, onpage optimization changes (from none or accidental to well-optimiized), and a change of address on a Bing listing that did not go through completely on Bing Local the first time. So, yes, the Bing/Yahoo drop in early March happened on a a few sites I monitor, and were very pronounced on one site that was undergoing many changes.   After waiting 2-3 weeks for things to index/deindex naturally with all search engines, this week, I submitted URLs to Bing Webmasters Tools looking for some ranking relief. Next step is to do some deep page linking to try to influence having more pages crawled by Bing.  I would be interested to hear others' experiences.

I agree with Heiko, it will not hurt your rankings. In this video you referred to, Matt says "all within the same domain"...so I guess you are concerned about having sub-domains. But sub-domains are still within the same domain.

Hi, Studio33. Yes, promoting discussion and exchange of ideas on blogs is usually the purpose of a blog. Commenting on blogs was previously used to boost SEO, but now the value is found more in the discussion participation, reputation, and calling attention to your own work. Just like you would not boast and manipulate conversation at a party, you do not want to do so on a blog comment either. But if a comment is relevant to the post and readers are likely to have interest, it is great to share your information...and if you get some attention from it, that is a nice benefit.

Do not be afraid to market your brand. If you are marketing in a respectful way with readers' interests in mind, you will rarely go wrong.

Hi, Ruben. When faced with choices like deciding whether or not to pursue support from a website with a low DA, I put aside my pure SEO hat and put on the more encompassing marketing hat. We often think about the Google and other search engine rules as ways of getting brownie points (or avoiding penalties). But if we think about these "rules" as just quality control regulations to help to determine which websites are most likely to provide satisfaction for a searcher's intent, then the answers are easier...at least to me. So back to your question...with my marketing hat on, I ask myself if  information on my website can be helpful to the visitors of the target website and if I think in the future that traffic/following on the new website will be enough to warrant me spending time to build that relationship. If the answers to those questions are "Yes," then go for it. It is unlikely that you will want to spend time on many low authority websites at one time since it is a bit of a gamble if your time will pay off in the future. So the low authority site will just be one link in a more robust and diverse portfolio.  I have found success in doing things for the business with a concern for maximizing SEO rather than doing SEO hoping for impact to the business,

Hope that gives you some ideas.

By providing Google Webmasters Tools with your international targeting information, you are helping Google decide if your website should appear and how it should appear (in local results) in a location. It only affects results for geographically related queries in which a user limits the scope of a search to a certain country.  It will not affect appearance in search results that are not geographically bounded. Hope that helps.