International SEO with .com & ccTLD in the same language

[gravityseo]

I've watched http://www.seomoz.org/blog/intern... and read some other posts here.  Most seem to focus on whether to use ccTLD, subdomains or subfolders.

I'm already committed to expanding my US-based ecommerce to Canada with a .ca ccTLD.

My question is around duplicate content as I take my .com USA ecommerce business to canada with a second site on a .ca URL.

1. With the .com site's preference set to USA, and the .ca site's geo preference (automatically) set to Canada, is it a concern at all?  About 80% of the content would be the same.  FYI, .com ranks OK in Canada now and I want .ca to outrank it in Canada.

2. I know 'localizing' content within the same language is important (independent of duplicate content), but this might not be viable in the short run given CMS limitations.  Any direct experience to help quantify the impact here between US and Canadian ecommerce?

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Adding:

I'm not totally confident here.  From this google webmaster central post it seems that canonical tags aren't needed.  I tend to think nothing is truly neutral and want to be confident regarding whether to use canonicals or not.  Is it helpful, harmful or harmless?  My site already has internal canonical tags and having internal and external would be a pain I think.

@Eugene Byun used it successfully, but would the results have been the same without?

Thanks!

[KeriMorgret]

Hi! We're going through some of the older unanswered questions and seeing if people still have questions or if they've gone ahead and implemented something and have any lessons to share with us. Can you give an update, or mark your question as answered?

Thanks!

[gravityseo]

Thank you!

[Eugenius]

I manage several multiple ccTLDs where English is the primary language (UK, ZA, AU, and CA). They are all using the same content as the corporate US site. We implementd the rel canonical element across the ccTLDs to point to the corporate site.  We haven't experienced any issues so far and the ccTLDs still rank well in their respective countries for our major terms.

I don't know if this is the most appropriate/effective strategy, so I'd love to hear how others would address the orginal posters issue.