During the last Page Rank update, few of us had problems with Page Rank splitting issue with GoogleBot thinking www and no-www version of your site as two different domains. So to tackle this menace, Google has added a new feature called Preferred Domain to its Webmaster Tools fleet.
Using this feature you can tell Google if you’d like URLs from your site crawled and indexed using www version (http://www.yoursite.com) or non-www version (http://yoursite.com).
Some people link to www version of you site, whereas some of them preferred the non-www version, So this tool will help Google determine your Pagerank more accurately (i.e Your page rank won’t split up). Once you set your preferred domain, it will take some time before Google crawls your site .The changes should reflect within a week or two, However it depends upon the size of your site and several other factors. If your using Plugins or .htaccess hacks to set a 301 redirection, you can safely disable it now.
How to set Preferred Domain ?
Preferred domain can be set by logging into your Webmasters Tools (Previously known as Sitemaps.
I welcome this new feature from Google and I have set non-www version of my blog as my preferred domain, because I support non-www.org. But I’m still having some problems with Webmaster Tools, I have to verify my blog each and every week using their Meta Tag. I don’t like to use their Meta Tag because it fails to validate, So I remove it once the verification is done. Maybe I should try the file upload method to verify my blog.
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wrote, on September 29th, 2006
[...] thilak pointed me to Google Webmaster Tools and helped me setup my Preferred Domain so that my Page Rank will be set to just one domain, the http://www.techzonline.net rather than both the http://www. and non-www domain. [...]
wrote, on March 31st, 2007
[...] tackle this problem, Google recently added a new tool into Webmaster Tools called preferred domain, which lets you choose between www and without www prefix, but that works for just Google. What [...]
wrote, on September 21st, 2007
[...] mirror pages.To tackle this problem, Google recently added a new tool into Webmaster Tools called preferred domain, which lets you choose between www and without www prefix, but that works for just Google. What [...]
wrote, on February 11th, 2008
It is very useful feature. If you use right robots.txt and Preferred Domain - there will no problems with wrong mirrors