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Mike, there is a technical solution specifically for this situation that will give you the best of both worlds! You're only considering moving the blog to a subdomain because you need to make management of the backend code more efficient and you're wondering how much of an SEO hit you'll have to accept in order to accomplish that. As EGOL says (and I fully concur), moving to a subdomain is going to do serious damage to the value of the both the primary site and the blog. What you really want is to have the WordPress install elsewhere, but still have it show to visitors (and search engines) like it lives in the /ecommerce-blog subdirectory. This is exactly what a reverse proxy is designed to do. It allows you to have the WordPress code installed on a subdomain, but still serve the pages to the visitor from the subdirectory as you have been doing. So to the user, the blog looks and works just as it does now, but the code is actually running off a subdomain. This can be a little tricky to set up, but as long as you have reasonable control over your server, and an experienced server administrator, it's not all that difficult. Especially in your case as you're replicating an existing structure so you won't need a whole slew of redirects. In fact, a reverse proxy could even be used to house the WP install on a completely separate server if you really want to separate the code from the ecomm code. If your site runs under the Apache webserver, reverse proxy is available as a fairly simple Apache module (it's the config that's tricky.) It's also doable under Windows/IIS but harder. (Note this typically can't be done on shared hosting, but as an ecomm site, I assume you're running on at least your own VPS server?) Here's a post from here on SEOMoz by PointBlankSeo for a little more background on reverse proxies. Hoe that gives you a second option to consider? Paul