So I've heard - I'll be trying Emirates sometime next year (it'll be especially nice now that they're flying the A380 from Dulles) and am already booked on the acclaimed Qatar Airways for my Singapore trip in late April.
I've heard the Asian carriers absolutely wipe the floor with their American competition when it comes to food and drink (and service generally). Some of the European flag carriers (BA, KLM) are still pretty decent.
BA is pretty grim in all cabins; Virgin in economy equally grim but PE is pretty good and Upper is great.
The Asian carriers are generally quite good but the best globally is Air New Zealand; their Economy is on par with other carriers' Economy Plus and their Business is close to the level of a non-suite First (but at business class prices, which puts them at #1 in my book). In a true First Class, Singapore wins but really, Emirates, Qatar, RJ, JAL, etc are all pretty amazing.
But all the Asian and Middle Eastern carriers are state subsidized and by deregulating, the US pretty much ensured that our airline standards would never be as high as they were before, despite the taxpayers still subsidizing the industry in the form of all those bankruptcies, bailouts and pension write-offs. Anyway, it's no real surprise that JAL or Singapore makes United look like an old shoe.