As you said blogs setup for different geo locations. Would it serve purpose if you redirect all of them to a single website/blog? I mean they must been for varied geographic targets.
I case you are contemplating to discontinue all of them and redirect them to one so that you can focus all your efforts at a single place then it can be a good idea but make sure you redirect (map) specific pages/posts to the corresponding new pages. Simply redirecting all the domains to a single domain will not help much. You should keep in mind the user comfort as well.
Regards
