Those fields are for possible future use, there is nothing yet in mojoPortal to determine the user location from ip address, but it is possible to do it. One way is using 3rd party data from various vendors, the one I've looked at is ipligence. They have free data that could be imported and used to associate a geographic location with an ip address, they also have more detailed data if you pay money. Google for "ip address geolocation" for more info. I created the mp_UserLocation table based on the idea of using the data from ipligence, but I never finished it.

There are other ways of doing it as well using various services including google, this blog post by Scott Hanselman has some info on that. 

At some point I may use one of these strategies to build it into mojoPortal so we can capture user locations and plot users on a map, but its not my top priority.