With many years of Map and Compass skills under my belt, I don't feel the need for one here in Adirondacks. There are so many known terrain features, that by using Triangulation, it's easy to find your location. The Ocean, Desert, Alaska, are quite a differant story though. Occasionally I'll bring a Altimeter if I'm expecting low visibility. My first experience with a GPS was is in the first gulf war. They were invaluable on the vast, featureless, unknown, terrain.
If I'm already carrying a map, Altimeter, and compass here in the Adirondacks, then a GPS to me, just seems to be an extra piece of gear that could be left behind, for faster more efficient travel.
More people should learn how to navigate correctly by map and compass first, then if they desire, add one to their gear list