I think it's mostly older people with GPS's that are keeping the mapping programs alive. Younger adults and such are using smart phones and Googel Earth/Maps for their trip planning.
It seems to me that people are getting more used to using one device for many uses, even though it does most of those things not as well as a stand alone device. Look how many people use cell phone cameras and are happy with lousy photos rather than use a regular camera and get good pictures. Or crappy downloaded MP3's rather than better downloaded MP3's or CD's. Many people just seem satisfied with mediocrity rather than preferring excellence. Go figure.