Flew an overnight, international flight yesterday and I couldn't have been more pleased with the service!

Announcements
Kept to a minimum, both in length and volume. I never heard the booming automated nonsense either ("The captain has turned on the fasten seatbelt sign).

Meal
Served with the cabin lights off (i.e., in the dark) so you could sleep! Executive Dining came with the appetizer, too! Breakfast was served without a cart, so as not to wake the sleeping people.

The thing I value most on an overnight flight is sleep. If UA can provide a more pleasant sleeping environment than its peers this will go a long way in keeping me loyal on routes where I can choose between airlines.