It was a bit late--just a few days ago--when I learned that Google had actually made an update of its Pagerank system and edited the respective PageRanks of each webpage in cyberspace. In truth, the update was made around last month, after previously updating in June 2009.
My personal blogs (not this one) remained their rating of PR 3 (out of 10), which was actually good enough for me given that I do not update them much anymore. But, seriously, how important is Facebook when it comes to your quest to come out on top of the Google search engine rankings?
First of all, PageRank is one of the technology behind Google's success. The Google founders, Larry Page and Sergey Brin, invented the technology to come out with the most relevant and accurate results for any search query. In a word, PageRank gives the search engine the opportunity to give value to websites for specific keywords and allow it to rank the results accordingly.
The entire Web is interpreted to be one large graph, where each website is a node that connects to other nodes via hyperlinks. These links are then assumed to be an equivalent of a citation in academic writing and is important to determining the PageRank.
Important and highly visited websites are given a high PageRank, and whichever it links to are, in general, given a portion of this reputation. This is because it is assumed that the linker suggest the linked website, also just like in academic writing. The Google PageRank, along with sophisticated text-reading technology, is used to determine the final order of the relevant websites when given a specific keyword.
Though really useful, there is no use forcing your website to improve your PageRank aside from creating relevant content and asking as much reputable websites to link to you. The grading system can be quite random, in my opinion. Sometimes they go up for no apparent reason, while sometimes they simply go down. It's all unexpected sometimes.