Google in all its infinite wisdom has deemed it necessary to have operator intervention when GPS is enabled. GB will not allow any app to initiate GPS. The only way to get around this is to root and run a custom ROM that has disabled this feature. I used to have my Tasker app automatically start GPS when I ran certain programs so I didn't have to, but GB ended all that.:'(
As to why they made this change, IDK? The only thing I can think of is that they want to be the only ones automatically recording your location data without your permission?? They don't want other apps to have the ability to just turn on your GPS and knowing exactly where you are without your knowing it. The other thing that suck about this is tracking programs that use special texts or phone calls to enable your GPS so you can find a lost phone are now disabled too. I was never one of those people but I can imagine they aren't very happy either.