The first thing I noticed when enabling the GPS receiver with Maemo Mapper and walking about for a while, was that the track recording wasn't very useful if you're going in and out of buildings, subways, or similar obstructions.

When in a constrained space such as on a narrow alley or street with high buildings or when the receiver is just warming up, it's common for the position to jump around on the map quite a bit, with a messy result also in the recorded track. Since the GPS receiver can also give an indication of its positioning accuracy, Mapper should take this into account and not treat the position information on the same detail level. I would suggest that the display would show a lower accuracy position as a larger circle and move it only when the new position data falls outside the boundaries of this circle. This would also "average out" the error data in the track record.