I've been wondering about this and would like to know what you all think. For one of my sites, I've been using a non www url for almost four years now. The SEO on it is sort of mediocre but wonder if I should change it to www.mydomain.com . Yes or no? Google has indexed all the sites pages as nonwww. Why I want to change it? Simply for aesthetic reasons. Yeah I know sounds dumb but I see a lot of major sites out there advertising with the www. The other side of me is saying don't touch jack and it won't matter because even if users type down www.mydomain.com they will see the page and that's all that matters.