Author here. I use Chocolatey too, although not so often recently.

Scoop is more focused on open-source command-line developer tools. I expect Scoop will appeal more to cross-platform developers, those who appreciate a bit of Unix philosophy in their spare time, and those who feel 'stuck' on Windows.

Chocolatey does a lot of things that Scoop will never do, like install Web Platform Installer apps, and built-in Windows features.

So I need to write chocolatey packages for non open source stuff? For example, I was about to add a package for Teamcity. So scoop doesn't encourage that kind of tools / software? Btw, I am not being critical of the tool. It is great that Windows is getting some much needed tools like this.

The 'extras' bucket for Scoop is a good fit things that aren't open source command-line tools, but are still useful dev tools. Teamcity should fit well there:

https://github.com/lukesampson/scoop-extras