Ted Chiang's The Lifecycle of Software Objects. What happens when support for the platform for your artificial mind is deprecated? (or in this case, your child's). Warning: heartbreaking.
This is the book I came here to recommend. If we ever get to true general AI's, I think the processes described in this book are likely how it's actually going to happen than anything more top-down. Also, like you said, a (good) gutpunch, too.
His first collection, Stories of Your Life and Others is also excellent. They don't technically fit the description of hard comp-fi, but they have a similar sensibility, even when they're dealing with magic and religion (which makes sense--his day job is technical writing).
