Will the same content on three servers be penalised?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Neil Cassels: Well you could always use a redirect on the .co.x ones to the .com/x 
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  Nishant Desai: Thanks +Neil Cassels ;for your suggestion.
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  Steve Kilbride: "Penalized"?  ;No.  ;But it would be duplicate content in the eyes of the search engines.  ;You want to avoid that since you'll have no control over which domain the engines will index for that particular content.
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  Jon Dunn: Like +Steve Kilbride says, you won't be penalised, but the dupe content will be filtered and not rank paticularly well.
  
  Why not have the same design/branding for the sites but different content? How many pages are we talking about? Is cost of rewriting pages an issue?
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  Federico Sasso: if you want to keep them all without redirecting, you could mark them with rel="alternate" hreflang="xx", it also works cross-domain
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  Nishant Desai: Thanks +Federico Sasso ;+Jon Dunn ;+Steve Kilbride ;