I had one of mine pop off the other day, the one on the center console, drivers side.

i was just turning it a bit to direct the airflow away from me and *POP* off it came in my hand! i didn't even put that much force on it, then as i tried to put it back in place i heard something fall into the heater/ac ducting and now it's just loosely haning in place.

anyone else have this happen?

guess when i go get my oil changed next week i 'll have the dealer fix it, but man it seemed like it was overly delicate.

When I first got my XB, I was experimenting with the passenger side center vent. I closed it, but thought it should close more securely, so I pushed a little harder and off it came.
Nothing broke off though, and it snapped back easy enough. They look like inexpensive parts to replace. Doesn't the Echo have the same vent thingees?