Fascinating to read how this thread developed in such hope and then came crashing down to the realisation that the LED light is there to act as a device notification only.
Green = charged (when plugged into a charger), Red = charging, Flashing Red = battery is low, Flashing Green + Red = Overheating.
This is the same for all Window Phones and is part of the inherent hardware design architecture. That's not to say it can't be changed but I doubt Microsoft will abandon their current thinking anytime soon. We already have the glance 'n' go nature of the Lock screen, highly customisable to show new notifications and missed calls etc simply by pressing the power button. Now I'm not saying this is the best it can be, I'm merely pointing out that it is already there albeit one momentary press away.
Nokia is responding to this way of thinking in Amber+GDR2 by introducing the double-tap to wake feature which incorporates a low light standby screen showing the clock and battery level. I'm sure this will develop over time and show effectively what the Lock screen already does.