Google recently updated its algorithm to take down Web sites that use SEO to game search results and up their ranking, but spam still dominates results. Search for something like "how to lose weight" and a flurry of content farms will appear.
Content farms simply hire low-paid freelancers to write articles about every topic in existence, allowing their Web sites to rank high in Google search results. The result? Unqualified, haphazardly written posts that can bury more reputable sources and delay the time it takes to get the answers you're looking for.
In response to these content farms, you can now permanently block Web sites from search results. Make use of this tip (in the video below)--Google is likely noting users' blocks to identify Web sites it should manually lower the ranking of.