Easily manage your Nokia Location API credentials across all themes and plugins on a site.
In short, very easily. But before you read any further, take a look at Asking For WordPress Plugin Help And Support Without Tears before firing off a question. In order of preference, you can ask a question on the WordPress support forum; this is by far the best way so that other users can follow the conversation. You can ask me a question on Twitter; I'm @vicchi. Or you can drop me an email instead. I can't promise to answer your question but I do promise to answer and do my best to help.
Yes. Really. At the time of writing (April 2012) 196 countries, 75M Places, 2.4M map changes a day. That sort of really. All available through a set of developer friendly APIs.
The Nokia Location APIs work if you don't register. But they work even better and you can do even more if you do register. Take transactional limits. Unregistered users of the Location APIs get 1 million transactions over a lifetime. 1 million sounds a lot but it soon mounts up. Registered users get 2 million transactions. Per month. Plus a whole lot more.
A disclaimer is in order. I work for Nokia's Location & Commerce group, that produces Nokia Maps. I see what goes into the map and what gets displayed. I'm very pro Nokia Maps for just this reason.
Totally; this plugin is licensed under the GNU General Public License v2 (GPLV2). See http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt for the full license terms.