I am fixing up the SEO for a friend's authority site. This person has never had any real SEO done but tons of potential. The issue is they have a dedicated mailing list they use with yahoogroups (it's been around for about 10 years), and it looks like google is indexing all of the yahoogroups posts, which are the exact same articles as the site. Is this a duplicate content issue i need to worry about, can yahoogroups articles be labelled noindex? or is this a blessing in disguise that i can use to leverage link juice? This person is an older person, and they're set in their ways. They want to keep yahoogroups. So any ideas outside of losing the yahoogroups mailing list is what im trying to do. Thoughts and opinions welcomed.