Those tags somewhat look like this and use to serve the purpose of telling search engines where the site is based:

<meta name="geo.placename" content="United States" />
<meta name="geo.position" content="x;x" />
<meta name="geo.region" content="usa" />
<meta name="ICBM" content="x,x" />

Google ignores them, and has for a really long time. JohnMu from Google confirmed this most recently in the thread:

We generally ignore geo-meta tags like that because we've found that they're generally incorrect (copy & pasted from a template, etc).

But we had confirmation of this when wrote that Bing relies on these geo-meta tags to determine a site's location. And time and time again, there are webmasters who find there site targeted to the wrong country because of that template issue. In that post, Google's Matt Cutts said the same thing:

Historically, meta tags for language and country have been less reliable than inferring the language or country directly. For example, lots of webmaster also just copy/paste from a friend's template without checking the meta tag values. The unreliability of the meta tags is why Google tends not to use them or give them less weight.

So three webmaster points here:

(1) Google ignore the geo-meta tag (2) Bing currently uses the geo-meta tag (3) Be careful when you copy templates or use pre-existing templates

Forum discussion at Google Webmaster Help.