We relied on it here so that bedtime was voluntary; my son was willing to go to bed at 7pm but I insisted he stay up longer. Didn't matter though as he was up and prowling downstairs at 1am, 1:30am, 2 and 2:30am.
He thinks that Santa stopped here twice because there were twice as many presents under the tree this morning than last night. As a result of all that anticipation I didn't get to sleep until about 5 this morning, and I am really dragging today!