Joel talks about the Law of Leaky Abstractions. I don't think anything new is in this, but the organization of all of it into one article is a Good Thing.

It's true that you have to have some balance between flexbility and encapsulation/abstraction. The more you abstract, the more you tie yourself down. Object-zealots used to preach that you could go infinitely into the object universe abstracting layer by layer, but this does you no good if something breaks on a lower layer and you don't know how to fix it, let alone recognize it is broken.

Maybe what is really needed are some reliable abstraction layers. Many of these already exist for Internet communication protocols. What if there was a single abstraction for a buffer? Couldn't we guarantee that software using this buffer wouldn't have buffer overflow errors?

Of course there's the issue of languages, and performance. Sometimes fast performance trumps explicit checking. But we could be getting into an age of software development now where performance takes a back seat to security and reliablility for once. Not for games or graphics obviously, but mainstream software development could benefit from it.