Understanding the way that search engines like Google and Bing crawl your sites for duplicate content is not always easy to follow. What exactly are the rules, and what are the ramifications for not following the rules?
This presentation by a group of industry experts focused on gaining an understanding of how search engines read your content, as well as what steps you can take to avoid penalization for your content.
Peter van der Graff: Redirecting Duplicate Content
We always assume that Google knows best, but is that necessarily true? According to Peter finding a formula that works 100% of the time is no easy task. He opened up with a great example “If you have a 301 redirect and you tell Google to go left, they’ll probably go right.” You could end up implementing a 301 redirect and when you request the location a cached version of the site may still appear instead of the redirect you intended.