I've had my Droid since day 1 of release. I have the GPS enabled for Navigation, but the GPS indicator (icon at the top) would not ever show unless I was using Navigation, Maps or some app that was actively using GPS. Over the last week or so I've noticed that every time I wake the phone from sleep that the GPS indicator is showing and remains there for a few seconds, then goes away. If I manually put my phone back into sleep mode, and then wake it up, it's there again. Sometimes it actually seems like it is off, then when I wake the phone up by pushing the power button it comes on it appears, then I unlock the phone and it turns off.
Current running apps:
com.android.providers.ap (then it is cut off. It has 0.00 for all of it's data/use/size)
com.android.providers.user(also cut off)
Google Services Framework
EngineService (Music Junk)
Google Messaging Service (Google Services Framework)
BluetoothOppService (Bluetooth Share)
BluetoothPbapService (Bluetooth Share)
Android Keyboard (Android Keyboard)
I killed the Maps Service and app, on a hunch, and it still does it. I am running a rooted 2.2.1 phone.