Our oldest daughter is eight, and she's just learning to iron. We began with pillowcases. She is enjoying ironing, so I will capitalize on that for awhile. I do think it's good for every child to have a stint at each household task so they become familiar with it, but I'm not into making them suffer through it if it's something they really detest. We try to utilize the strengths we have around here, so I tend to give organizational jobs to one child who's really good at that sort of thing and babysitting jobs to those who enjoy babysitting, etc.
When I mentioned her ironing to a friend, she told me she has her girls learn to iron on their play dresses. What a great idea!