Is .COM the best domain extension for Search Engine Optimization (SEO)?
A question asked to me via email last week... Here's the answer:
Overall, Domain name is still pretty important from the SEO perspective. Even though each search engine ranks the importance of domain names differently.
At the macro level, domain name extensions (.com, .tv, .mobi, etc...) don't actually have any negative SEO impact - if you registered a .com and a .tv on the same day, they should hypothetically rank the same (all other factors being equal). The reason why .com's rank higher normally is because they have been available to register since the 1980's, and hence are the oldest - not only are old domains more likely to have links pointing to them, but age of a domain is also a point in Google algorithm (mentioned in one of their patent filings).
There is one area where domain name extensions can affect search rankings, and that is for geographic-centric search. Google does tend to give preference to "local domains" - hence, if you perform a search on Google.ca, it is more likely you will see .ca domains than if you perform that same search on Google.co.uk (which would emphasize .uk sites more than .ca sites). You don't need a .ca to define your site as Canadian though; through the Google Webmaster Tools you can define your website's audience as Canadian even if your domain extension places you in another country.