well, not even my two cents, one, at best, considering that i don't have a N9 (& most likely never will get one...) but...

based on the N8, which has a (tiny) led as well next to the micro-USB port, it strikes me as not very useful if that was to blink, unless the Nx is... lying on the side with the LED staring right at you.
simply not placed well for that purpose (notification)...

but, hey, that's a (happy) N900's camper PoV