You can tell I'm from Kentucky because I don't know how to say everyones name. I'm going to try: Jochen from Stuttgart in Germany asks: „How do meta geo tags influence the search results?“
And the answer is that it is not something that we look at very closely at all, not meta geo tags. We tend to look at the IP address, we tend to look at the gTLD or the ccTLD – thats the country-code-top-level-domain, so .fr, .de. There is also something in Google's Webmaster Tools where you can say: “my site is not just a .com, it's about the entire world”, “it's a British .com” or “it's a .com that really pertains to New Zealand or Australia”.
So you can highlight and say: “Ok, this .com is really about Germany, or Canada, or whatever your country is”. But typically, the geo tags that are in meta tags are not as useful and we don't tend to give those as much weight, if at all.
So I would spend your time trying to make sure you have the right domain name, trying to make sure you have the right IP address if you can and then definitely, if you have, content that is geo located, even if it's a subdomain or a subdirectory, you can specify that within Google's Webmaster Tools and say: “Yes, this is relevant for this particular country”.