Hi,
From my experience working on International brands, where you have the one brand and you do SEO on say 20 different TLD's as it is a global SEO project.
I would try to have localized content for the markets, I mean if you want to have a maximum effect in the market you really need to target GEO specific content for each market. you have the treat each website seprate, you have to do SEO for each specific market. For example on the .co.uk website you build links from the same local market.
Sure enough the core elements of the websites can be similar yet I would best advise to use as much localised content as possible.
In the end of the day Matt Cutts, Answer to this question is not the best. I have seen people burnt over hiring a UK SEO agency when their website is located in Australia and they only use .co.uk for the link profile, use the wrong spelling for a huge amount of words on the websites and target terms, it was a real night mare hence they are now looking for AU based SEO's.
Kind Regards,
James.