International multidomain structure

how to structure an international site across multiple domains?

[danbot]

I have a .com.au website that services australia. Over the next few months I am planning to expand it to service the entire world. I am wondering how best to handle this.

One thing I guess I am worried about is having hundreds of thousands of pages that have the same layout with slightly different/varying content. I think I am already pushing the limits on the hazy line of what is regarded as spam. But currently google does not seem to mind.

I am thinking that I should spread my service for the rest of the world across a couple of other domains. .co.uk and .com. I would then have a link on every page with an option to switch between countries (domains) each of which provide content for seperate regions. (UK, US and AU).

Is this a recommended approach for dealing with this sort of situation? Or should I keep everything on the one domain?

[bill]

Splitting things up onto different domains for different language groups or different markets is the recommended way to go about it. Some people are recommending local hosting in addition to a ccTLD.

[danbot]

What is the recommended way of interlinking these domains? Taking into account possible google ranking penalties?