Google Sidewiki launched
This is an extension of Google's personalised search and 'search wiki' option launched at the end of 2007, which allows users to adjust their own search results and add comments against ranked websites. The new Sidewiki tool now takes this a step further by giving users the chance to share knowledge, experience or advice against web content.
In developing Sidewiki, Google says that a priority was for users to see the most relevant entries first, so they have developed a system to rank the comments that are added in the 'best' order. So, instead of displaying the most recent entries first, the Sidewiki ranks entries using an algorithm that promotes the most useful, high-quality entries. It takes into account feedback from users, previous entries made by the same author, and many other signals they have developed and tracked.
This should help to address the obvious concerns of website owners that competitors will post negative comments and reviews against their web content, in much the same way that review based websites have been trying to deal with competitive 'spam'. There is also the ultimate question of how the tone of comments will be used by Google in the long term to have another impact on the relevancy of search ranking results.
Another feature of the Sidewiki is that the technology will match comments about a web page with other websites where the same content is displayed. This will help to broaden the value of the system and to reduce the need for duplicated comments or posts. Google is also going to use relevant posts from blogs and other sources that talk about the specific page of content so that users can discover their insights more easily, right next to the page they refer to.
Google Sidewiki is being made available as a new feature of the Google Toolbar so you need to download the latest version to access this sidebar and add or view comments. It's still going through a beta stage of development and Google will be improving and enhancing this feature in the coming months. You can also view more information about this tool here: http://www.google.com/sidewiki/intl/en/learnmore.html