My diagnosis is Asperger's Syndrome (and ADHD), but since that is on the autistic spectrum anyway, I am by logical implication autistic.
I prefer to call myself autistic when speaking to the general population (in my country, hardly anyone except for the ooccasional geek has heard of Asperger's Syndrome anyway, so I don't use the term often); when I am with aspies who know what that means, I call myself an aspie.
I kind of like saying I am autistic because I like seeing people's reactions. It has been a particularly positive thing sometimes, because some people whose nephews or children or whatever are autistic don't feel comfortable talking about it normally, and when someone states it as boldly as I do, with no shame or embarassment but rather with great glee, it's like a big weight off their shoulders to know they can talk about it as openly without all the support-group misery usually associated with "conditions".
In South Africa there are no weird discriminatory laws against autistic people like there are in some states in America -- not that I am aware of anyway -- so saying I am autistic doesn't bar me from anything.
_________________
When I must wait in a queue, I dance. Classified as an aspie with ADHD on 31 March 2009 at the age of 43.