Duplicate Content & Urls

Hi all

I have a question that has been bugging me for a while, so I thought I’d get an expert opinion.

Basically, the company I work for has 2 domain names - www.companyname.co.uk and www.company-name.co.uk. They are separate sites - i.e. one doesn’t forward on to the other - but they have exactly the same content. We don’t have to update both sites though - if a change is made, the change is reflected on both sites.

My question is this: will Google see this as duplicate content? My colleague says no, because you can specifiy in Webmaster tools which domain name you want to be the default. But I’m not sure I go along with this - it seems to me that if you have 2 websites with the same content, Google will see 2 websites with the same content and may choose to penalise us. Or at the very least, they’ll essentially be competing against eachother for rank surely?

I’d appreciate any comments or advice ….

Thanks,
Smartie