This article sure is timely. I've been working on a ruby project for a while now and I'm just about to get it live. The key for me was two things: 1. Forking. Sounds silly, but man oh man did this increase performance. 2. Relying on a unix tool instead of going with a ruby gem.
Now I admit that I'm locking myself into a unix environment, but I really don't have the time or skills to make this project OS agnostic. If it is an eventual success, I may have to pay off some of that technical debt, but that is a problem I wouldn't mind having.