If you are finding that the www.sitename.com and sitename.com version of your site are both being indexed by the search engines you could hit an issue with the search engines seeing duplicate content – after all most sites have both site names resolving to the same underlying file structure. This can also be an issue for people with parked domains – if you’ve brought multiple domains with the common misspellings of your company name (for example), if the search engines index the parked domain you could have a duplicate content issue. Another issue is having links pointing to the various site names dilutes their value, but pointing them all at just one domain name you’ve got a better chance of higher rankings.… Read the rest