I have played around with the tools, but what really stood out to me was how easy it was to get them installed. While the author does provide install instructions, the VM is ready to go in only five steps (two if you already have vagrant and virtual box installed).
I have used Vagrant in the past and it makes managing VMs very easy. If you are distributing a developer tool, make it easy to get up and running by letting the user download a virtual environment that is correctly configured. Then trying out your software becomes a 30 second test, not a 10 minute test.
Of course, the author of Data Science at the Command Line is not alone. I noticed Ionic is providing a VM for android development too. It looks like Vagrantcloud lets you share virtual instances with the world as well.
Frankly, I used to download and install cygwin first thing on every Windows computer I bought. But VMs are so easy now it’s easier to just install VirtualBox, Vagrant and a version of Linux (CentOS or Ubuntu).