I'd like to move all my media files to a CDN (Windows Azure is my best choice for now). Two questions :How can I avoid SEO and redirections issues for the previously uploaded media files ?For the next media files I'll upload, isn't using a CDN bad for SEO and search engine ranking ? 
Concerns about moving media files to a CDN and impact on SEO
media;seo;cdn
It is? Putting all our images over on Amazon Cloudfront was the only way that we were going to get our images indexed by Google and keep our customer happy by having a responsive server that wasn't wasting time serving images instead of pages. The media server cname was registered with Google webmaster tools, any search term I enter has quite a few high ranking images over in the image search which, since Google originally found them on our main website, provides a nice link back to the page where they were found. It all ties together if you do it right.