From my recent trip IAD-AUH-SYD in Y (yes, this is not the most efficient way to go from IAD to SYD... but it was the second part of an open jaw booking and this made sense at the time). Overall I was happy with the amount of food, although the taste and presentation leaves something to be desired.
IAD-AUH - 12.5 hour flight (B787), received a normal tray meal after departure and prior to arrival, both with choices. I think the first had two meat choices and vego, and the second might have been only meat and veg. Both meals had a small side (cheese/crackers) , dessert, etc, on the tray. In between, the only offering was a packet of Lays potato chips. No bottles of water were offered, only water poured in a cup, although the meal trays had a tiny water cup (80 ml or less, almost useless).
AUH-SYD - 13.5 hour flight (A380), received a normal tray meal after departure with two meat choices (vegetarians were only catered for if they had a pre-selected special meal). There was an in-between snack which was a chilled cheese sandwich with a small dessert (apple pastry) - a good upgrade over the Lays. The final meal before landing was a hot selection also with only one choice (chicken pasta), with slightly reduced sides. Similarly, no bottles of water were offered - many Sydney-bound travelers expected this and complainted to flight attendants, as this is standard on other longhaul airlines serving Australia.
Also, none of these meals contained Western "breakfast" style selections (e.g. eggs/omelette/etc with sweet muffin/pastry), even though in both cases the final meals were in the morning based on the origin time zone. Of course, with varied cultural backgrounds on the passengers, this is not really that significant.
On each segment, a different passenger near me was trying to eat vegan, but in one case had not made a special meal selection, and in the other claimed she had, but flight attendants said it was not on file. As most of the vegetarian choices had dairy, staff did their best to find food from staff or business class meals where possible - even though this appeared to be user error in at least one if not both cases.
One thing I liked is that they serve drinks with the same cart as the meals, and got to it reasonably quickly after departure - none of this faffing around with a snack, then a drink service, and finally what seems like hours later, get around to the main meal. Also, the meal trays were cleared reasonably quickly, rather than being stuck there for another hour like Qantas. On overnight sectors, every minute of sleep opportunity is prized, so the hustle is appreciated.
On the AUH-SYD segment (A380), I tried to order from the "sweet" section of the buy on board menu, which was supposed to be done using the seatback screens, but the system said the facility was unavailable. I didn't inquire of staff if there was a way to manually order and just gave up on the idea. But they certainly aren't going to be selling much if they don't turn this on. Maybe the selections weren't even loaded. I didn't see anyone else appearing to order or consume anything from this menu.
On another note, I was very happy with the first class lounge in AUH. Nice job Etihad to provide Virgin Platinum members this amenity. Such a constrast to some OW carriers like UL that don't even provide OWE members access to a decent business lounge ...