Today was due to see the last ever passenger flight on a 747 from the US by a US carrier, Delta's DTW-ICN flight DL159. But, it was canceled because one of the pilots no showed.
You'd have thought that Delta would have taken special care to ensure this momentous flight ran as scheduled, especially as many passengers would have booked solely because of the occasion. But unlike United they don't seem to care much for the 747, and certainly don't care much for Boeing at the moment. The flight is now rescheduled for tomorrow and will return after a quick turnaround at ICN, so the last ever 747 flight by a US airline will still run, though late.