They should incorporate some piezoelectric generators into the steps like I've seen recently, then make them charge a capacitor that would power the LED's for a few seconds. Then it would be self sufficient.
I hate the artificial-looking light that white LEDs give off. If they made this with red LEDs (which don't ruin your night vision nearly as much) and pointed them directly down, then this would be very very nice.
Ummm.. The stairs dont freakin light up at all. All I see is motion senor leds that someone installed in the stairwell. it rould be cool if the "stairs" light up when you walk on them however motion sensor may not work but a pressure sensor would.