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As far as rewriting goes, you want to pick one version of your site, either www or non-www, and stick with that so that, when you get links, they point to the correct address. When you don't rewrite your URLs, it looks to search engines like there are actually 2 websites, the www version and non-www version, that display duplicate content. I'm guessing that you selected the www version in Google Webmaster Tools because that is the only one it displays. Regarding fixing it, your domain registrar and host will sometimes have a simple setting for that actually so that you don't have to do a mod_rewrite. If you don't find anything with your registrar/host about it, you might be best served by posting a new question here about it. Regarding keywords, that's a tough one, but like many SEO issues, we'd like to think the rules are hard and fast, but they're not. You're not supposed to be able to get by with keyword stuffing – as your competitors apparently are – but it happens. There might be a newer version of this video, but in 2009, Matt Cutts talked about the fact that Google doesn't use keywords as a search ranking factor. watch?v=jK7IPbnmvVU