Using Google to search the web is not a complete look at the web as it is in it’s entirety, but rather a comprehensive look at what Google has found, analysed and indexed from the web. It’s is Google’s priority to provide users with the best, and most relevant webpages in light of the context of your search.
Since it’s inception Google’s made a number of changes to it’s system to further ensure user search satisfaction is achieved. In early 2011 Google announced the Panda update which incorporated artificial intelligence and human quality like measurements of any given website. In essence this brought to the forefront the usability of a website. In my experience it became apparent that any website representing a brand, product or service benefited, whereas websites seemingly lacking trustworthiness and featuring duplicate content suffered. It has been stated that the importance of a website’s page-rank is now less of a factor or influence, but is it’s continued use in typical, successful link building activities suggests to me that the value of the page-rank is far from removed Google’s judgement factors …yet.
The Google Penguin update has been more about spam or black-hat related issues & penalties. For some louder members of the SEO community this has been at a sacrifice of the good search results and the user experience of Google search. Website’s with a number of ‘web-spam’ or ‘black-hat’ linking issues have been penalised and from what I have experienced, ‘questionable-advertising’ at the top of a webpage is also a target in the most recent Google algorithm update.
SEO continues to evolve, and so does our use of the world wide web!