Originally Posted by lock

When other search engines offer the same keyword domain different extension then the backlinks may actually work in google. Submit a dot com and a dot other into all the exact same promotion same keywords same everything use identical sites and watch the dot com rank faster and better all round. Why because not every site will except other extensions giving less backlinks giving lower ranking. Assured or not whether SEO works the practicality is the result.
Just the ping results alone will show that some other extension may fail translates to less backlinks, On obscure keywords and odd subject anything will rank but on popular keywords the difference will show.