Moore's law has actually been failing as of late. I suspect that exponential increase in computer capability is a feature of the yet-nascent state of computer technology. Assuming that it will continue into the foreseeable future is a bad idea. Performance is important; it's just not as important as some think, and in particular, it's not so much all-around performance as the ability to avoid bottlenecks that's important. This is why a profiler for arc would be nice, as would some easy and standard way to hook into a lower level language for speed boosts.