Brad Wilson points to a Dave Thomas post on development:

Dave Thomas has a great blog post talking about language performance. He's talking about Ruby, but his points are universal. It's no secret that I'm in love with dynamic languages in general, and with Ruby in particular. The performance question is one that always comes up early. Ironically, the people asking this question are usually coming from a managed environment like Java or C#, which were subjected to the same questions by C++ junkies. Talking about business apps in general, and web apps in particular, Dave really nails this:

Let's face it: your average commercial application isn't burning CPU cycles solving NP-complete problems. We typically write code that moves chunks of data about and adds up a couple of numbers. In these scenarios, is it worth worrying about the relative performance of the language used to do the moving and adding? Not in my book.

That's something I was getting at the other day in this complexity post - most people aren't writing apps that do huge amounts of number crunching - heck, most people aren't doing apps where anything more involved than a linear search is necessary. And yet, there's an obsession with trivia - like the speed of floating point math. If you'e one of the people for whom that matters, sure - you want a language that optimizes well. Everyone else - you want a language that optimizes at the end that actually matters - developer speed.