I could see this as a option to turn on, and off where you select he map viewing method. (map, satellite view...), and a option in the settings, to start the maps application with the GPS on, or off.
Also, I'm not sure, but I think that he version for the symbian s60v3 (non touch screens) has that feature.
In my experience, GPS positioning drains the battery VERY FAST (2-3 Hours max on my nokia 5800) so when I’m walking all day, I can’t turn on the maps, and left them in the background like I’d do with a regular map, that i would have all the time ready to look at. Now I have to constantly turn the map application on and off (and wait a minute or two, before i can use the map itself, because it's waiting for a fix every time, and that freezes the map mode). I think that this should be rather easy to implement, and could give an advantage to the project.