Hi,
Will try not to make this too long! My 16 year old daughter was diagnosed as autistic last week, I haven't had a final report yet however she would definitely be classed as high functioning/Asperger's.
A lot of the questions that I was asked about my daughter during this process have led me to look at myself and my own childhood, and how I am as an adult. I did initially think that maybe she had got it from her dad, but now I'm not so sure!
To start with, I have 3 sisters and have always been considered the black sheep - weird/odd if you like! A bit socially inept and a bit of a loner, very happy in my own company while craving the acceptance of others. Very non cuddly. Basically fit the profile in terms of social chit chat, bluntness etc. I could go on but it would take ages!!
The part about obsessions also chimes true, I've had a lifelong obsession with horses, also reading, and as a sideline have been obsessed with saddles for about the last 5 years, I could reel off a tonne of information about it all day long and the obsession doesn't get old- it's so stupid but I can't help it, it's almost like a compulsion!! Sidelong obsessions I've also had have been around arbitrary objects such as sewing machines or tents- I'm basically an expert on a load of crap inanimate subjects that NO ONE else is interested in 
I won't go on any further now, but wanted to hear from anyone who was diagnosed as an adult? I've read that people say it doesn't help, however for me I think it might actually explain away the feeling of being odd that I've had for my entire life.