He forgets to mention one critical fact: developer productivity. Most applications (sans his terrible example of protein folding) are not that performance critical. Most of the code you write as a developer will do-away with any platform or language advantages itself.
It is not productive to write web applications in Java. Everyone hates it, which is why we have ruby, php, and now javascript (node).
I'd much rather trade a little performance for a scripting language anyday.
I wonder if someone has written up comparisons on their productivity between the languages / frameworks. My previous job had me on the python stack (Pyramid / Mako / Sqlalchemy), which I loved, but have been on Java / Play! framework for the last 10 months. The one thing that has consistently surprised me is how productive I feel writing Java. Mainly, I notice I make far fewer mistakes / typos while coding; the IDE does a great deal of the work for me, and as the application grows, having static types has (for me) improved the readability of code I haven't looked at for a while.
No doubt a large part of any language choice is subjective, but I'm starting to believe that developer productivity has more to do with the tools and frameworks than the language itself. As these continue to improve in Java-land, I'm willing to bet that the disparity in productivity will continue to decrease.
>The one thing that has consistently surprised me is how productive I feel writing Java.
I know exactly how you feel. I recently moved from a Java project to a Python one and felt a little amiss without the power that an IDE gives a statically typed language. The tooling for Python flat out sucks. And it pains me to say, as I love the language to death, but I do feel more productive in other languages. Whether or not that's true is another thing entirely, but it does feel like a lot of time is wasted calling `dir` on objects to figure out what the hell the name was of the function you need.
As of about a week ago I switched from my text editor + console to Eclipse + PyDev. It's not perfect -- intellisense functionality is really hit or miss, but it does make me feel a lot more productive. The background linting is pretty good at catching basic errors as you type them, which is really nice.
It's also does an OK job at renaming things -- which is generally a nightmare to do on a big project in Python.
So, point being, while I miss a lot of the other tooling that an IDE affords a statically typed language, PyDev gets you, like, 80% of the way there. Worth checking out if you move back to Python.
I don't; that's a bit of a sweeping generalization. I happen to enjoy writing webapps in JAX-RS and Wicket, and I know a number of folks who enjoy writing them in other frameworks.
It is not productive to write web applications in Java. Everyone hates it, which is why we have ruby, php, and now javascript (node).
I'd much rather trade a little performance for a scripting language anyday.