This article from about a month ago demonstrates the overlap and fuzzy lines between all these labels. I think people are becoming more educated and comfortable with the word "Autism" and distinguishing parts of the spectrum may become less necessary. In a sense PDD-NOS can describe anyone on the spectrum better than any other label since there are so many things we just don't know. Honestly I prefer to describe myself as having mild Autism over Asperger's. It just sounds better. Technically my original diagnosis on (after severe ADD and other "alphabet soup") was Semantic Pragmatic Language Disorder on the Asperger's Spectrum. I never heard that term again after that. I did go home and looked it up online and was only confused due to all the overlap and contradictions. These labels are just a "necessary evil" to identify patterns anyway. They are not absolutes or permanent marks on people's souls. I'm just waiting for a new euphemism to come out. Maybe in time the word "Autism" may go the way of the Sony Walkman.