Asperger's comes up differently on brain scans, not to mention that many symptoms are different than High functioning autism in mannerisms from stress and over all behavior in public. In my own experience as a female with Asperger's and my brother with it as well have met people with High functioning autism that behave strikingly different from us.
Aspergers should not be considered a syndrome. Aspergers is an autism spectrum disorder. It is a neurological condition. A person with Aspergers has a brain that is wired differently that a neurotypical person. People with Aspergers have no physical difference in their appearance than an average person. Therefore, it is not like looking at a person with Downs Syndrome where you can tell they have a syndrome simply by the way they look.
Asperger's Syndrome is not a syndrome or a disease. It is a part of the autism spectrum. Though children and adults with Asperger's seem to be more asocial than non Asperger's they are able to see things differently. People with high functioning Autism can have a higher IQ than most "normal" people. I don't think Asperger's Syndrome is a true disorder. It is a genetic trait much like race and gender. Autism has its difficulties. But so does being "normal".
Asperger's Syndrome is an ASD (Autism Spectrum Disorder), but it should be treated as an individual diagnosis because a simple mild autism diagnosis is not specific enough. Asperger's is one type of HFA (High Functioning Autism), but there are other types of HFA, such as PDD-NOS (Pervasive Development Disorder - Not Otherwise Specified). If Asperger's Syndrome had a specific diagnosis as a type of ASD, the information for the diagnosis would be more specific, which would allow differentiation between other types of HFA.
No, Asperger's Syndrome should no longer be a diagnosis or a "syndrome." I say this as a person who is diagnosed with Asperger's Syndrome, or rather, who was previously diagnosed. The diagnosis is now "Autism, High Functioning" as research has shown that there is no need for a distinction between high functioning Autism and what was previously called "Asperger's Syndrome."