I installed wp from fantastico it gave directly url without www like http://google.com There is an option with wp to keep the site url as http://www.google.com Which one is better for SEO in wp I want to know what my friends here are doing ?
I'm not familiar with doing it in WordPress, in any case this should be applied sitewide as there are possible duplicate content problems. You will need to do this in the .htaccess file in the main directory of your server. This mod rewrite guide will tell you what to do. I redirect all my sites to the www version.
In my experience it really doesn't matter. Furthermore in regards to google you can set which url it uses and displays, as to ward off any fears of duplicate content. In regards to setting your preferred domain.