After setting up the IoT XDK, I decided to try out the blink example. Excitedly, I saw that the LED on pin 13 was blinking just as expected! But when I attempted to change the interval from 1000ms to 100ms and 3000ms, there was no difference in the blinking pattern. Even after reuploading to the Edison and tweaking the app version info, the light stubbornly continued to blink every second.
It seems like I'm overlooking something simple here.