Optimizing doamins for different countries?

How can I best optimize my domains for each country, without creating a bunch of duplicate content, and thereby lowering my overall rank?

I own several domains under different countries for my business, such as mybusiness.com, mybusiness.eu, mybusiness.ca, mybusiness.co.uk, and so on. Right now, I only operate the .com domain. Soon, I'd like to light up the other domains, and create websites customized to the nature of the country that's being targetted. Most of the content will be simular to the main .com domain, and a little will be different (contact info, shipping policy, ect).

Right now, my .com domain ranks well. When I copy most of this content to the other domains, and suddenly create a bunch of duplicate content, it seems like that I'll be watering down the SE strength of my .com domain. How can I best prevent this?

Thanks.

That really is the billion dollar question and probably one of the hardest things to do right.

For a start I'd say go with a Geo-Location cloaking system which will serve the relevant language to the relevant IP based on their Geographical location.

But depending on exactly what you need could differ from the above

Google now state that having duplicate content on different TLDs so as to target regional versions of Google will not result in a duplicate content penalty, however, I recently tested this and a penalty ensued.

I had content on a .co.uk targeted for the UK which was working very well. I then developed a .com.au version of the site and made some minor modifications to the text to account for local dialect and published this on a Au based IP block.

The UK site rankings (and PR) dropped and the AU site never really got going. After removing the AU site, things on the Uk site reverted to pre AU performance.

>>How can I best prevent this?

Totally unique content per URL and host them on a localised IP block.

Do not interlink the sites.

Google will still know that they are linked through whois records so you may even wish to use localised records for those too by way of virtual office in the host country or the like.

In a recent post Matt Cutts talks about cloaking and geolocation.

He states that serving different content based on the visitors IP address is within Google's quality guidelines.

I've never tried this though, so if you do, please report back with your findings.

Anybody else here tried this?