Thanks for the comment. The canocial tag (like 301 redirects and the meta you mention) is mean as another hint to search engines to index the correct, unique. It’s another sign you can send (I’d advise doing it alongside and method such as 301 redirects or using the method I described in a previous post on www. and non www. versions of your site) to search engines saying where the correct content is located. For the effect required to implement this into something like wordpress or your own website, I think it’s definately worth it.

It’s also worth nothing that overall you’re not only trying to help users, but also consolidate your page rankings from multiple urls, to a single one – teherby avoiding duplicate content penalties.

I personally believe as many methods we have to prevent duplivate content, the better. For example, to manually integrate the canocial into your wordpress install the process is quite pain free – there’s an excellent simple article here on how edit WordPress to prevent duplicate content (you only have to edit your header.php file – simple!)

There, I wrote way too much again for a comment reply