Want to optimize referral traffic while at same time keep search engines happy and the ads posted. Have a client who advertises  on several classified ad sites around the globe. Which is better (post Panda), having multiple identical urls using canonicals  to redirect juice to original url? For example: www.bluewidgets.com is the original www.bluewidgetsusa.com www.blue-widgets-galore.com Or, should the duplicate pages be directed to original using a 301? Currently using duplicate urls. Am currently not using "nofollow" tags on those pages.