A penalized web site is much less likely to show up in a SERP, and in some cases it may not appear at all. The Google sandbox effect The expired domain penalty Duplicate content penalty 1.The Google Sandbox Effect Many search engine optimization experts hypothesize that there is a virtual “purgatory†that all newly launched sites must pass through in order to rank well in Google. In fact, many new sites seem to pass through this stage, and many find that the period is remarkably close to six months. Matt Cutts states in an interview with Barry Schwartz that there may be “things in the algorithm that may be perceivedas a sandbox that doesn’t apply to all industries†(http://www.seroundtable.com/archives/002822.html). I believe that while Google may not explicitly have a “sandbox,†the effect itself is real. For this reason it is termed an “effect,†and not a “penalty.†It may be the collective side effect of several algorithms —not an explicit “sandbox algorithm.†Some sites seem to be exceptions to the rule, especially those that acquire links from several authority sites early on. A few links from CNN.com and other prominent web sites, for example, may exempt a web site from the sandbox effect. Some hypothesize that Yahoo! has a similar algorithmic factor, but that it is less severe and pronounced. Bing Search does not appear to have anything similar implemented. 2.The Expired Domain Penalty Using a previously expired domain to launch a new web site used to evade this dreaded “sandbox effect.†This was likely because Google was unaware that the site was new. Google put a stop to this loophole a while ago, and now it seems to be quite the opposite situation at times. An expired domain name may now be subject to a temporary penalty. This is important, because it implies an additional delay before a site begins to rank well. In some cases Google will even refuse to index the pages at all during that period, leaving a web site vulnerable to content theft. It is also likely that Google devalues any links that are acquired before the re-registration of the domain. 3.Duplicate Content Penalty Search engines attempt to avoid indexing multiple copies of the same content—duplicate content. Many search engine optimization experts hypothesize that not only does a search engine not index such pages,but it also penalizes a site for having the duplicated content. This is a subject of much debate, but in any case, having duplicate content will not improve the rankings of a site in any of the major search engines. Therefore, duplicate content should be avoided.
This "penalty" does not exist. You only have to look at a large news site to see that many of the articles are from a single source; there is not special rule for them over any other site, the duplicate content penatly does NOT exist in this manner. http://www.im-wizard.com/clearing-up-the-duplicate-content-myth/ Any "SEO expert" that does not understand this is not much of an "SEO expert". The only time it might exist is duplicate content appearing on the /same/ website.
Does the duplicated content affect your site negatively if it's from an article that is linking to your site from many different directories?
Another potential google penalty to consider is that triggered by building too many links too quickly or too many links with same anchor text.