I don't know if I have this, but when it comes to my boyfriend, I'm of the opinion that he's better off keeping it to himself. I'm hugely proud of him, and while in an ideal world, people should be understanding and accommodating, that's simply not reality. I can imagine people discrediting him, as noted earlier in this thread. I do wish, however, that he'd said something more at the start of our relationship, because "I take things literally" was nowhere near sufficient, and caused a lot of unnecessary hurt and confusion for us both. Telling partners early on is a definite must.
Somewhat amusingly, his mother is one of those people who I believe would try even harder to convince him that he might enjoy something that he's always avoided if he just tried it. Though I wonder whether she would say the same to her partner, who is very shy, and spends the majority of his time in solitude working on an interest that has led him to become quite well-respected for his vast knowledge in an extremely narrow, specific field... I don't know whether she's pieced it all together, but I find it interesting that the person pushing for normality has the most ties to AS (it's very obviously from her side of the family).
Still, I think its wise to be careful who you tell. People aren't going to understand unless they want to, and the majority simply can't be bothered.