Just a hyptothetical...
Bob wants to start a new series of sites, each very similar in structure but each targeting a different country. Using australia as an example, the site would use australian terms, list everything in australian dollars, have australian adverts, only show casinos that accept players from australia, have the geo-target set as australia and get links from australian sources.
The sites would each have custom content written and there would no problem with duplicate content, just a similar design, structure and back end.
Should Bob:
1. Create separate sites on new domains for each, with the potential for ccTLDs where possible (eg: australiacasinos.com or casinos.com.au)
2. Create a master site and use sub-domains for each country (eg: australia.casinos.com)
Both methods allow the sites to set different geo-targets in GWT, and (if you were so inclined) can be hosted in the relevant country.
To be honest I think that there are benefits to both methods from both SEO and branding, so I'm really just asking - what would you do if you were bob?