The risks of dying from measles are extremely small, especially if you're otherwise healthy. The death rate dropped massively before introduction of measles (single) vaccine.
The lifetime cost of severe autism is over 3 million per individual. My son (severely autistic) will require 24 hour care for the rest of his life. The majority of MMR affected individuals appear to be affected severely. Even if only 7% of cases are triggered by MMR, the costs to the state are enormous. Even HFA costs the state a lot (financially) and for life.
To see autism as some sort of shrug the shoulders 'at least they're not dead' thing is crazy. I don;t agree with kerry in that I don;t think severe autism masks my son at all- his personality and who he is shines through, but it has robbed him of the chance of any sort of choice in life at all. He can't do anything without help. Aged 8 he can't stand outside his own front door without an adult holding him. There are very very few activities he can access, he can't go for a picnic, he can't go to the cinema, he can't ride a bike, he can't play on a computer, he can't go to theme parks (even with help- for all those activities)in addition he is reliant on someone else 24/7 and it will always be like that. His disability will have a profound effect on the childhoods of his brothers, Which is why for childhood at least we'll take the risk of measles for ds2 and ds3 (and I'm well aware they're not risk free- my mother is deaf in one ear from measles), then if they haven;t caught it go for singles at puberty.
The mirror neurone stuff is interesting cotedazure- I susepct its relevant for a reaosnably large number of people with autism, especailly at the lower funcitoning end (inlcuding my son)- imitation has a profound effect on abilities and socialisation- as we found out when ds1 learned to imitate aged 7- it's made a huge difference. I think its an area worth persuing. Autism is often very much a biological system, but how all the bits relate together soon gets very complicated. The brain/gut stuff is just starting to be investiaged and I'm sure will prove fruitful.