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I have a client whose site did not use the www preference but rather the non www form of the url. We were having trouble seeing some high quality inlinks and I wondered if the redirect to the non www site from the links was making it hard for us to track. After some reading, it seemed we should be using the www version for better SEO anyway so I made a change on Monday but had a major hit to the number of pages being indexed by Thursday. Freaking me out mildly. What are people's thoughts? I think I should roll back the www change asap - or am I jumping the gun?