Stop using "autism" and "retarded" as insults. Jesus. English is a wonderfully diverse and varied language. You can find a word that isn't insulting to people with disabilities.
You would have to be the most sensitive of the sensitive to get offended over others being called an autist, honestly, if someone is acting as someone with autism would - it is an apt description, wouldn't you agree?
Personally, I'm against people insulting eachother all together, but arguing over something as silly as this is dumb.
Why can't we all just be friends ;_;