I don't know about the 09 &10 vibes, you didn't say what year you had but on the 03-08 Vibes, the ones that do have the illuminated cig lighter outlet, it should be lit up the same as the backlight for the AC/defogger/hazard/blower switches and the shift indicator (on AT vibes), which is that it should be on whenever the tail lights are on, but it's brightness is controlled by the dimmer switch (by the exterior mirror controls)
Thank you for the welcome. Love my Vibe and shouldve thought about joining this sooner! . My Vibe is a 2009! I've just never noticed that ring illuminated before and it kinda concerned me. :/
Like joatmon said, its only on when the parking lamps/headlamps are on.
On a side note, the drivers side window switch "AUTO" is constantly on anytime the car is on; lights OFF or ON. The dimmer control does not control the brightness on the "AUTO" light switch or the steering wheel controls (if you have them).