Actually, i think it's different from selecting the "wait" command.
I've let it happen a few times to see, and the durability can go down more than 1 (The first time you select wait, you will always lose 1 durability, then 2, then 3, and so on).
And if i'm not mistaken, the color of the orb doesn't change when you let the timer run down, you only lose durability.
Ahh, my mistake. I was 99% sure I read that it was the same as wait, and the one time it did happen to me, I only lost 1 durability.
As for the color not changing: It doesn't *always* change when waiting either, so unless you've let the timer run down several times, it may be that it does change the color.
Just tried it in game, letting the timer run out definitely does still change the color. The durability hits I took also line up with twice the durability I would lose for a wait (so I lost 2 if I hadn't waited yet, and on a separate attempt, lost 4 for letting the timer run out after waiting once).
Not that it matters much anyway: There's no good reason to let the timer run down. Edited, Oct 25th 2010 6:02am by Ilmoran