Newly diagnosed young adult son - how to embrace and approach things!

Despite knowing deep down for a very long time, our 20 year son was yesterday officially diagnosed as Autistic.  On telling him, the assessor congratulated him and said the world would be a better place with more Autistic people in it! I felt very emotional yet positive on hearing him say those words and our son, well I think he is in some ways relieved.

What I would like to ask people now, is how to take things from here. It will be up to our son of course, who he chooses to tell, but I don't want him to think we are hiding it or keeping it a secret. A friend of mine when her 12 year old son was diagnosed, they had a little party.. our son is too old for that, but i want to acknowledge it and how proud we are in some ways.

Where do we take things from here?