Irony in motion:
Restaurant Quality In-Flight Food
Now I've only had the pleasure of having J food once on QF, which was at least 8 years ago now. The service was good (especially on upper deck), but the food was very, very much average. They had duck with rice or fish steak with vegetables. The duck was about 50% fat (including skin) and the rice - well, it was edible but let's not talk about that. The man next to me had the salmon steak with veggies. The steak looked like it had just been in the freezer and thawed out (not that it was, of course, but it looked like it. You could almost misteak it for a pink brick). I think the man took a few bites and left a lot untouched. Couldn't blame him - I wonder how much taste the dish had altogether anyway.
Fact of the matter is no one is going to get a great feed on board. Food is really just there because if there wasn't, then a lot of people would get irritable indeed. Not only that, a few people might go pale and etc. etc...you get the idea. As someone else said, if I wanted a decent meal, I'd go to a restaurant or cafe. (For me, at least the food on board is better than the food in our university canteen - ugh! - so that's good enough for me!) I'm still surprised at some of the reports here, since if I ordered a "steak", even in J, I'd still be expecting something comparable to the sole of a leather shoe (but that doesn't mean I can't be impressed...)
As for the coffee on board, at least it is brewed. Most of the time they get it right, but sometimes they do burn the mixture so the coffee ends up tasting rather ............ Of course, it isn't as good as a nice espresso (which only the First classes get), but then again many people can't prepare a good espresso either (e.g. by burning the beans, etc.). And at least it isn't instant - that stuff not only kills you slightly faster than eating burnt toast, but (most of the time) it's just plain revolting.
The food I've had in the last twelve months of flights has been decent. I managed to get the same sets of meals on two different flights, which I found disappointingly quaint.
My maxims for in-flight meals:
1) If you're vegetarian and you didn't special preorder, you're screwed. You're especially screwed if you're vegan or fruitarian. (Hence, I am not either

)
2) Never take the seafood. It's never prepared well.
3) Lowest common denominators if you really hate the main meal: cheese, crackers, rolls and milk (protein and carbs that'll see you through). If you like, throw in some salted nuts.
P.S. QF J class food > MH J class food