Regarding Zhang's age: Most Fields medalists these days are very close to exceeding 40 years. Wiles himself just a special silver medal, because of that - which I think is outrageous age discrimination. Mind you he didn't get the silver medal because his results were a bit less spectacular than those of the winners, but rather they were so groundbreaking he couldn't be ignored, but because he was just over 40 they ha…
Maybe we just need a new Nobel in math.