Nowadays I always say 'I'm Autistic' (officially diagnosed with Asperger's syndrome), but I'd be fine with being described as 'on the spectrum'. Whereas I don't feel comfortable with 'person with autism' (referring to me, I completely understand that that might feel right for someone else). I see the spectrum pretty much exactly as Nat sees it in his blog post, if you asked me to draw the spectrum I would have drawn a colourful circle - or the prism light experiment (I see a metaphor for invisible disability in the way the prism is see through and you don't see the colour until you shine the light on it, because I'm overthinking this way too much. And obviously some people have a very visible disability).
I fit very neatly in a box labelled 'high functioning' with no buts...but I don't like the term, because it's not very useful for a lot of other people. If you have a high IQ but are mostly non-verbal, can't live independently and write your very insightful and extremely well constructed blog about your life on your godsend-of-an-iPad because it's the only way you can express your thoughts to others, or if you have a clutch of A's and A*'s in all your exams but haven't left the house in 3 years, well, in what way does 'high functioning' help describe your condition? Functioning is a word we automatically associate with the ability to do the day to day things most people take for granted being able to do, whether that's talking, or visiting a packed Tesco on the big weekly shop, not a word we automatically associate with IQ.
I remember telling someone I was autistic in secondary school, and getting the reply that they thought it was overdiagnosed these days...which I interpreted as they didn't think I had it. I quietly and shyly challenged her, but I felt too confused and dismissed to do it robustly and tell her how wrong she was. Some people also seem to associate the word high functioning with 'over diagnosed', just another way to minimise the challenges people have in their lives.
I don't have a visible disability. I have some issues with certain areas of communication (small talk, expressing thoughts in words and subtle non-verbal communication), but really in terms of communication I'm not impaired. I used to be. It's not that I've 'grown out of being autistic' (for instance my obsessions/obsessive thoughts, anxiety and strange repetetive movements have become more and more pronounced as I've got older, as my social/communication difficulties have decreased). I still score as being above the autisitc line on online quizzes. It's that I'm a good actress, I am empathetic, I deeply want friendships and company and when I have a script, or even just a basic pattern, I rarely find it difficult any more, because that pattern becomes safe, predictable and then automatic, which also means little or no anxiety. So you might well talk to me and watch me talk to other people and then be surprised to learn I'm autistic. But if someone's going to say there's not a thing that's atypical about me based on that and 'it's overdiagnosed', then there's a part of me that likes to imagine if they saw me rocking, flapping and pacing, and their face as they run away from the freak as fast as possible...just a part. In reality, whilst pacing and flapping and rocking feels wonderful, comfortable, 'right' and frankly joyful at times, I feel such embarassment or shame if someone sees me.
In terms of special abilities, my prepared answer is Yes I do, and in fact I was even invited to attend a school for people with special abilities, but after I took a look at the death and injury rate there I declined Professor X's kind offer.