The magnetic pole does move from time to time. The movement has a lot of implications. For example, as the magnetic pole moves, the amount of declination changes for a given area. Declination is the difference between the compass reading pointing to magnetic north and geographic north. For example, here in Colorado, the declination is about 10 degrees East. People using a compass have to correct their heading by 10 degrees or they'll soon be very far off course. To put it in perspective, a 1 degree error will cause someone to be a mile off course after traveling 60 miles, so a 10 degree error is very significant. If the magnetic pole changes sharply, the declination values on maps and charts will have to be updated.

Another thing that I wonder about is the effect on migratory birds. Many migratory birds have a form of built in compass that they use for navigation. Will a significant change in the magnetic pole disrupt migratory patterns? Seems possible to me.