The ‘Find Me’ location feature in Google Maps on the iPhone and iPod touch is great, but if you are in an area with wireless access points that have yet to be mapped by Skyhook (the company that provides the location-acces point data for Apple), your shown location will rely upon cellphone tower position alone and so be far less accurate.

Recently, Jazzdogg on the Australian MacTalk forum contacted Skyhook with regard to manually submitting the longitude/latitude of his own access point to improve the location feature.

read it here macosxhints.com