I recall watching the GPS to the geocache locations go down from 15ft, 10ft, 6ft, 3ft, 2ft, and being very impressed with its accuracy. I must have been provided great coordinates to start with. Whatever it is, it's been a real positive experience and great way to start out. Almost all my 10 finds have been in open sky though.
I have had 2 GPS units over an 8 year period. In the past, I have only used them to find general landmarks out on the Alaska tundra (camp, airplane pickup, etc..). Out there, where a person can see 3-5 miles in every direction, pinpoint accuracy is not that important. Via geocaching, I'm seeing just how accurate a GPS can be - very cool.