The glovebox port doesn't stay powered when the car is off. As for the console port, it definitely stayed powered for a few minutes after I turned the car off and locked the door, judging by the charging indicator on my mobile hotspot. It might turn off after a longer period of time, but it remained active longer than I was willing to sit there and watch -- and like you I didn't want to just leave it there long-term and potentially drain my battery (or find it had shut off and then not know how long the cutoff is).
Likely selling end of 2015:
11 M3 E92 Le Mans | Black Nov w/ Alum | 6MT | Premium 2 | Convenience | 19" | EDC | Prem Audio | Moonroof | BMW Apps | Yoko AD08 R | Vorshlag Adjustable Camber Plates | StopTech ST-60 380mm BBK | Castrol SRF Fluid | ModMyNav.com rear camera | ECS Tuning Sunglasses Holder